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ACTINYL ION CRYSTAL CHEMISTRY AND ITS IMPACT ON STRUCTURAL

TOPOLOGIES AND ENVIRONMENTAL FATE

A Dissertation

Submitted to the Graduate School

of the University of Notre Dame

in Partial Fulfillment of the Requirements

for the Degree of

Doctor of Philosophy

Jessica M. Morrison

Peter C. Burns, Director

Graduate Program in Civil Engineering and Geological Sciences

Notre Dame, Indiana

April 2013

Jessica M. Morrison

ACTINYL ION CRYSTAL CHEMISTRY AND ITS IMPACT ON STRUCTURAL

TOPOLOGIES AND ENVIRONMENTAL FATE

Abstract

Jessica M. Morrison

The modern study of the actinide elements began more than 70 years ago, yet much remains to be explored about how these radioactive elements behave in complicated systems like the soils at Department of Energy sites, the forests near

Chernobyl or the ocean waters off Fukushima. The fundamental study of actinide chemistry provides a basis for understanding the mechanisms that control actinide migration in the environment.

Here two major themes are presented in which one explores the structural properties of U(VI) uranyl germanates as they relate to U(VI) uranyl silicates and the emergence of cation-cation interactions as a structural feature, and the other offers a glimpse at the behavior of Np(V) and U(VI) during the growth of rock- forming minerals for the purpose of understanding the inorganic controls of crystal growth on environmental remediation.

Hydrothermal synthesis and single crystal X-ray diffraction were employed in the study of U(VI) uranyl germanates. For the study of Np(V) incorporation into Jessica M. Morrison rock-forming minerals, a variety of room temperature syntheses were conducted before a simple synthesis in aqueous solution was devised. Characterization methods included ICP-MS in solid and solution modes and XPS.

This research demonstrated (1) the structural differences between U(VI) uranyl germanates and silicates by introducing new (VI) uranyl germanate compounds with uncommon structural features, like cation-cation interactions and chains of GeO5 tetrahedra; and (2) the potential for structural incorporation to play a role in neptunium mobility in the subsurface by showing that calcite has a higher affinity for neptunium than gypsum during synthetic growth.

To my grandmother, Daisy Rowe, who never learned to read; to my mother, Linda Dalton, the only one of fifteen siblings to complete high school;

to my nieces, Madison and Annabella, who will inherit the moon;

to my husband, Brandon, for everything else.

CONTENTS

FIGURES...... vi

TABLES ...... x

PREFACE ...... xiii

ACKNOWLEDGMENTS ...... xiv

CHAPTER 1: INTRODUCTION ...... 1 1.1 History and Usage ...... 2 1.2 Rationale for Study ...... 3 1.3 Overview and Scope ...... 8

CHAPTER 2: RESEARCH DESIGN AND METHODS ...... 10 2.1 Inorganic Synthesis Methods ...... 10 2.1.1 Hydrothermal Synthesis ...... 10 2.1.2 Ambient Synthesis ...... 11 2.1.2.1 Evaporation ...... 11 2.1.2.2 Diffusion ...... 13 2.2 Materials Characterization ...... 16

CHAPTER 3: STRUCTURAL OVERVIEW OF HEXAVALENT URANIUM GERMANATES AND SILICATES ...... 22 3.1 Introduction to the Crystal Chemistry of Hexavalent Uranium ...... 22 3.2 Overview of Germanium and Silicon Occurrence, Coordination and Structures ...... 25 3.3 Structural descriptions of uranyl germanates ...... 27 3.3.1 Sheets containing isolated tetrahedra ...... 27 3.3.2 Frameworks containing isolated tetrahedra ...... 27 3.3.3 Frameworks containing dimers of tetrahedra ...... 28 3.3.4 Frameworks containing chains of tetrahedra ...... 28 3.3.5 Frameworks containing rings of tetrahedra ...... 29 3.4 Structural descriptions of uranyl silicates...... 34 3.4.1 Sheets containing isolated tetrahedra: The uranophane-group minerals ...... 34 3.4.2 Sheets containing rings of tetrahedra ...... 37 3.4.3 Frameworks containing isolated tetrahedra ...... 37 iii

3.4.4 Frameworks containing dimers of tetrahedra ...... 37 3.4.5 Frameworks containing chains of tetrahedra ...... 38 3.4.6 Frameworks containing rings of tetrahedra ...... 38 3.5 Discussion ...... 45

CHAPTER 4: SYNTHESES, STRUCTURES, AND CHARACTERIZATION OF AN OPEN- FRAMEWORK URANYL GERMANATE ...... 48 4.1 Experimental Section ...... 49 4.2 Results ...... 59 4.3 Discussion ...... 62

CHAPTER 5: U(VI) URANYL CATION-CATION INTERACTIONS IN FRAMEWORK GERMANATES ...... 64 5.1 Experimental Section ...... 66 5.2 Results ...... 83 5.3 Discussion ...... 87

CHAPTER 6: CONTROLLED NUCLEATION AND GROWTH OF CALCITE IN AN AQUEOUS SYSTEM ...... 91 6.1 Synthesis Review ...... 92 6.1.1 Aqueous-Inorganic ...... 92 6.1.2 Organic-Mediated Aqueous-Inorganic ...... 92 6.1.3 Template/Seed Aqueous-Inorganic ...... 93 6.1.4 Mechanical Modification...... 94 6.2 Experimental Section ...... 94 6.3 Results and Discussion ...... 99

CHAPTER 7: INORGANIC CONTROLS ON NEPTUNIUM MOBILITY IN THE SUBSURFACE VIA CRYSTAL GROWTH ...... 105 7.1 Methods ...... 110 7.2 Results ...... 117 7.3 Discussion ...... 123

CHAPTER 8: CONCLUSIONS AND FUTURE WORK ...... 128 8.1 Importance of this research ...... 128 8.2 Uranyl Germanates ...... 129 8.3 Neptunium Incorporation ...... 130

APPENDIX A: PROFESSIONAL DEVELOPMENT ...... 132 A.1 Publications ...... 132 A.2 Media Contributions ...... 132 A.3 Invited Lectures and Engagements ...... 135 A.4 Conference Attendance and Presentations ...... 135 A.5 Professional Memberships ...... 137 A.6 Students Mentored ...... 138 A.7 Outreach ...... 139 iv

APPENDIX B: SYNTHESIS CONDITIONS FOR EXPERIMENTS ...... 140 B.1 Uranium Germanates ...... 140 B.2 Rock-Forming Minerals ...... 185 B.3 Maya Reimi’s Summer Notebook 2011 ...... 196

APPENDIX C: URANIUM DATABASE PARAMETERS ...... 212

REFERENCES ...... 264

FIGURES

Figure 1.1 The actinide series highlighted in blue...... 1

Figure 1.2 Actinide series oxidation states with the environmentally-relevant oxidation states highlighted in green. Those predominant under oxidizing conditions are shown with diagonal lines...... 6

Figure 2.1 Photo of u-shaped glass tube used in hydro-gel synthesis ...... 14

Figure 2.2 Photo of open-ended glass tubes used in hydrogel synthesis shown with 50-mL centrifuge tubes for scale...... 15

Figure 2.3 Derivation of the Bragg Equation ...... 17

Figure 3.1 Node representation (left) for Cu[(UO2)(SiO3OH)]2(H2O)6 with uranium polyhedra shown as filled circles, silicon as open circles, vertex-sharing as a single line and edge-sharing as a double line. Polyhedral representation (right) where uranium pentagonal bipyramids and silicate tetrahedra are yellow and blue, respectively...... 24

Figure 3.2 Polyhedral representations of U(VI) germanates containing isolated tetrahedra, dimers of tetrahedra, chains and rings of tetrahedra. The corresponding compounds are listed in Table 3.1. Uranium(IV) is shown in red, U(V) in orange, U(VI) in yellow and Ge in magenta. (Pages 33–34) ...... 32

Figure 3.3 Polyhedral representations of U(VI) silicates containing isolated tetrahedra, dimers of tetrahedra, chains and rings of tetrahedra. The corresponding compounds are listed in Table 3.2. Uranium(VI) is shown in yellow and Si is shown in blue. (Pages 43–45) ...... 42

Figure 4.1 Infrared spectra for three uranium germanate compounds with Cs2[(UO2)(Ge2O6)](H2O) in green. Spectra for the other two compounds, shown in blue and magenta, are presented in Ling et al. 2010 but are not discussed here...... 53

Figure 4.2 Thermal gravimetric profile for Cs2[(UO2)(Ge2O6)](H2O) ...... 54

Figure 4.3 Powder X-ray diffraction patterns for Cs2[(UO2)(Ge2O6)](H2O), its TGA residue after heating to 900ºC and the simulated pattern from the single- crystal structure...... 55

Figure 4.4 Fluorescence spectra for three uranium germanate compounds with Cs2[(UO2)(Ge2O6)](H2O) in green. Spectra for the other two compounds, shown in blue and magenta, are presented in Ling et al. 2010 but are not discussed here...... 58

Figure 4.5 Polyhedral representation of the structure of Cs2[(UO2)(Ge2O6)](H2O): One-dimensional chain or uranyl polyhedra bridged by Ge4O10 rings. Uranyl and germanate are shown as yellow and blue polyhedra, respectively...... 60

Figure 4.6 Polyhedral representation of the structure of Cs2[(UO2)(Ge2O6)](H2O): Three-dimensional [(UO2)(Ge2O6)]2- framework with channels extending along [100]. Uranyl and germanate are shown as yellow and blue polyhedra, respectively. Pink balls represent cesium cations, water molecules are omitted for clarity...... 61

Figure 5.1 IR spectrum for NH4(UO6)2(UO2)9(GeO4)(GeO3(OH))...... 73

Figure 5.2 IR spectrum for K(UO6)2(UO2)9(GeO4)(GeO3(OH))...... 74

Figure 5.3 IR spectrum for Li3O(UO6)2(UO2)9(GeO4)(GeO3(OH))...... 75

Figure 5.4 IR spectrum for Ba(UO6)2(UO2)9(GeO4)2...... 76

Figure 5.5 UV-vis-NIR spectra for five NH4(UO6)2(UO2)9(GeO4)(GeO3(OH)) crystals.77

Figure 5.6 UV-vis-NIR spectra for five K(UO6)2(UO2)9(GeO4)(GeO3(OH)) crystals. ....78

Figure 5.7 UV-vis-NIR spectra for five Li3O(UO6)2(UO2)9(GeO4)(GeO3(OH)) crystals.79

Figure 5.8 UV-vis-NIR spectra for five Ba(UO6)2(UO2)9(GeO4)2 crystals...... 80

Figure 5.9 TGA for K(UO6)2(UO2)9(GeO4)(GeO3(OH))...... 82

Figure 5.10 Polyhedral representation of the crystal structure of 4. (a) Projected along [100]; (b) a slice of the structure at c = 1/2 projected along [001], showing the U(2), U(3), and Ge polyhedra only. U(1), U(2), and U(3) polyhedra are colored green, magenta, and orange, respectively. Ge polyhedra are shown in blue. The Ba position is indicated by a cyan sphere.85

Figure 6.1 Photograph (top left) and schematic (top right) of the apparatus for synthesis of calcite crystals from aqueous solution. Beaker shown is 80 mL.96

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Figure 6.2 The photos above were taken from a video of an experimental trial in which purple dye was added to the initial saturated solutions of CaCl2 and (NH4)2CO3. The photo on the left was taken after 540 m and calcite crystals have appeared on the lip of the 2-mL vial that was initially loaded with (NH4)2CO3. The photo on the right, taken after 1260 m, shows abundant calcite crystals on both vials. The strong coloration of the solutions in the 2- mL vials demonstrates that complete solution mixing has not occurred in the system...... 98

Figure 6.3 Scanning electron microscopy images (collected at 200x) of calcite crystals grown from aqueous solution in the apparatus (Fig. 6.1) for initial beaker solutions ranging from pH = 2 to 6. Superior crystals were obtained when the initial aqueous solution added to the beaker was pH = 2 (upper left)...... 100

Figure 6.4 Measured pH of the aqueous solution in three different beakers as a function of time. The synthesis experiments began using the apparatus shown in Figure 6.1, with pH = 2.2 adjusted water filling the larger beaker. The measured pH values of standard solutions are shown by black dashes. The three colored lines represent the approximate pH of solution through the region of rapidly changing pH. The error bars applied to the beaker measurements are one standard deviation of the measurements for the pH = 7 standard, which averaged 7.03...... 102

Figure 6.5 X-ray powder pattern (CuK radiation) for crystals of harvested calcite. Peaks arising from calcite and vaterite are labeled. Two scales are used so that the full intensity of the calcite peaks are visible...... 104

Figure 7.1 Image from Reeder et al, 2000, suggesting three models for (UO2)2+ in the structure of calcite based on EXAFS characterization. Uranium, carbon, and oxygen are shown as cyan, black, and red balls, respectively...... 107

Figure 7.2 ICP-MS solution results for CALCITE showing actinide concentration in ppm versus reaction days. The top graph represents duplicate trials at 400 ppm (“low”) initial actinide concentration. The bottom graph represents 1000 ppm (“high”) initial actinide concentration. Error bars were based on uncertainties calculated from the standard deviation of the measured intensity...... 118

Figure 7.3 ICP-MS solution results for GYPSUM showing actinide concentration in PPM over reaction days. The top graph represents duplicate trials at 400 ppm (“low”) initial actinide concentration. The bottom graph represents 1000 ppm (“high”) initial actinide concentration...... 119

Figure 7.4 Time-resolved Np-237 laser ablation results in a calcite solid. Np-237 values shown in counts per second...... 120 viii

Figure 7.5 ICP-MS solid results for CALCITE and GYPSUM. Parts per million values represent an upper limit for the concentration of An in the solid material. 122

Figure 7.6 In the trigonal structure of calcite, Ca2+ is coordinated by six monodentate CO32- triangles. In nature, Ca2+ is commonly replaced by Mg2+, Sr2+ and Fe2+.125

Figure 7.7 Structural models for Np(V) incorporation into calcite where (left) NpO2+ is coordinated by four CO32- triangles and charge is balanced by excluding one CO32- triangle for every two NpO2+ included; (middle) the neptunyl ion is absent, Np5+ is coordinated by six CO32- triangles with two extended bonds and four short bonds and charge is balanced by excluding three Ca2+ for every two Np5+; (right) both configurations are present creating no vacancies and offering the highest incorporation potential with charge balance provided by the inclusion of three NpO2+ for every one Np5+...... 125

Figure 7.8 In the monoclinic structure of gypsum, each Ca2+ is coordinated by six oxygens of SO42- groups and by two water molecules. In nature, Ca2+ is not commonly substituted in gypsum...... 126

Figure 7.9 The structural model for gypsum requires SO42- groups to move in a way that would break down the integrity of the structure. The rearrangement results in bond breakage that would change the structure from two neptunyl ions coordinated by four monodentate and two bidentate SO42- groups to two neptunyl ions coordinated by two monodentate and four bidentate SO42- groups. For charge balance, one Ca2+ would fill interstitial space for every two NpO2+ included...... 127

TABLES

Table 1.1 Isotopes of select actinide elements with half-lives and decay mode (Morss et al., 2006) ...... 5

Table 2.1 Attempted mineral synthesis by evaporation and diffusion for actinide incorporation studies...... 12

Table 2.2 Procedure for Crystal Structure Determination ...... 19

Table 3.1 Hexavalent Uranium Germanates ...... 31

Table 3.2 Hexavalent Uranyl Silicates ...... 40

Table 3.3 Hexavalent Uranium Germanates and Silicates by Polymerization ...... 47

Table 4.1 Crystallographic data for Cs2[(UO2)(Ge2O6)](H2O) ...... 51

Table 4.2 Selected bond lengths (Å) for Cs2[(UO2)(Ge2O6)](H2O) ...... 52

Table 4.3 Bond valence sums for Cs2[(UO2)(Ge2O6)](H2O) ...... 56

Table 5.1 Selected Crystallographic Parameters for Compounds 1-4...... 69

Table 5.2 Selected interatomic distances (Å) for compounds 1-4 ...... 71

Table 7.1 Synthesis parameters for U- and Np-doped calcite and gypsum...... 112

Table 7.4 Interval pH measurements for U- and Np-doped calcite...... 114

Table 7.5 Interval pH measurements for U- and Np-doped GYPSUM...... 115

Table B 1 Lithium Uranium Germanates ...... 141

Table B 2 Potassium Uranium Germanates ...... 147

Table B 3 Sodium Uranium Germanates ...... 152

Table B 4 Rubidium Uranium Germanates ...... 153

Table B 5 Cesium Uranium Germanates ...... 154 x

Table B 6 Ammonium Uranium Germanates ...... 156

Table B 7 Magnesium Uranium Germanates...... 157

Table B 8 Calcium Uranium Germanates ...... 158

Table B 9 Strontium Uranium Germanates ...... 159

Table B 10 Barium Uranium Germanates: ...... 160

Table B 11 Mixed Based Uranium Germanates ...... 161

Table B 12 Description of selected uranium germanate materials...... 163

Table B 13 Cesium Uranium Nitrate Germanates ...... 169

Table B 14 Description of selected materials...... 172

Table B 15 Rubidium Uranium Nitrate Germanates ...... 174

Table B 16 Uranium Germanates ...... 177

Table B 17 Sodium Uranium Germanates ...... 179

Table B 18 Potassium Uranium Germanates ...... 181

Table B 19 Rubidium Uranium Germanates ...... 183

Table B 20 Synthesis conditions for calcite by precipitation/evaportation...... 185

Table B 21 Synthesis conditions for cerussite by precipitation/evaporation ...... 186

Table B 22 Synthesis conditions for barite by precipitation/evaporation ...... 187

Table B 23 Synthesis conditions for celestite by precipitation/evaporation ...... 188

Table B 24 Synthesis conditions for anglesite by precipitation/evaporation...... 189

Table B 25 Synthesis conditions for witherite by precipitation/evaporation ...... 190

Table B 26 Synthesis conditions for strontianite by precipitation/evaporation ..... 191

Table B 27 Synthesis conditions for gypsum by precipitation/evaporation ...... 192

Table B 28 Synthesis conditions for calcite by precipitation/evaporation ...... 193

Table B 29 Original synthesis for calcite and gypsum in tetramethoxysilane gel ... 194

Table B 30 A selection of synthesis carried out in straight, open-ended glass tubes195

Table C 1 Uranium Database Parameters ...... 213

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PREFACE

Through what could be called a diversion, I’ve studied the earth under my feet, I’ve created in days what takes nature thousands of years to fashion, and I’ve learned to see at the atomic scale while thinking on a global one. This experience – this process of deep, focused scientific discovery – is one that I will take with me as I go forward into a new experience: journalism.

The communication of science is an effort that requires attention from both scientists and the media. The voices of scientists raised up have the power to shape policy, transform technology, and change lives, but scientists can’t be expected to carry this burden alone. Through my experience at the University of Notre Dame and my passion for journalism, I have already become, and will endeavor to continue to be, a bridge between science and society.

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ACKNOWLEDGMENTS

I would like to acknowledge my advisor Dr. Peter Burns who took a chance, pushed me when I need it, pulled me when I stalled, and supported me when I realized that journalism was my calling. You have my gratitude and my respect.

Thank you to Jennifer Szymanowski and Tony Simonetti for all your help and patience.

As part of a growing lineage of environmental mineralogy and crystallography PhDs at the University of Notre Dame, I would like to thank those who’ve gone before me, worked alongside me, and are to follow behind.

I thank Tori Forbes, Amanda Klingensmith, Ginger Sigmon and Daniel Unruh for their guidance and support, late nights and early mornings, and above all, their stellar examples of what it means to be a research scholar.

I thank Amanda Albrecht, Christine Wallace, Enrica Balboni, Kristi Pellegrini,

Miller Wylie, and Brendan McGrail for their camaraderie at the University and in travel.

Best of luck to Travis Olds, Tyler Spano, Mateusz Dembowski, Ewa Dzik, Yi

Liu, Philip Smith, and Melika Sharifironizi as you continue on in your studies.

I thank also the post-docs with whom I’ve crossed paths: Jie Ling, Christian

Lipp, Jie Qiu, Zoulei Liao, Laurent Jouffret, Zhehui Weng, and Aaron Lussier.

xiv

Finally, I thank the undergraduate and high school students with whom I’ve had the privilege of working and guiding: Kelsey Poinsatte-Jones, Laura Moore-Shay,

Amanda Siemann, Christopher Schreyer, Maya Reimi, Dana Lind, and Rachel

Hoffman.

This research was supported by funded by the United States Dept. of Energy,

Office of Biological & Environmental Research, Subsurface Geochemical Research program, grant DOE-DE-SC0004245 and the Chemical Sciences, Geosciences and

Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S.

Department of Energy (DE-FG02-07ER15880).

CHAPTER 1:

INTRODUCTION

The lanthanide and actinide elements comprise the two rows that lie at the bottom of the traditional periodic table. Seen in Figure 1.1, actinides occur as a result of the sequential filling of the 5f electron orbitals. This means that an electron is being added to the outermost electronic subshell of each actinide element progressing from actinium, which has no 5f electrons, through lawrencium, which has a completely filled 5f shell. Of the 15 chemical elements with atomic numbers 89 through 103, all are radioactive due to the instability of their nuclei.

Figure 1.1 The actinide series highlighted in blue. 1

A discussion of uranium and neptunium will be conferred with regard to their origins, properties and interactions within the framework structures of germanate compounds and the local structural environments of selected mineral phases. Although difficulties arise in handling these elements due to their radioactivity, the actinides require independent study because they are unlike any other element group.

1.1 History and Usage

The study of actinides has a rich history with the bulk of its expansion attributable to the development of weapons during World War II. Before the 1940s, only actinium, thorium, protactinium and uranium were known. Elemental uranium was first recognized in 1789 by Martin Klaproth, but it had been used since the First

Century, CE, to produce yellow color in ceramics and glasses.

Two events occurring during the first half of the 20th century ushered uranium into a state of simultaneous reverence and apprehension. During the

1920s, the extraction of uranium began at Shinkolobwe mine in the Democratic

Republic of the Congo. Nearly twenty years later, the discovery of nuclear fission, the process by which heavier atoms are split into lighter ones, led to the development and subsequent use of the first nuclear weapon by the United States.

These events spurred an indirect interest in actinide science that started a nuclear arms race and initiated the development of nuclear energy technologies throughout the developed world.

The actinide scientific community has been active in exploring and implementing nuclear technologies for both peaceful and defense-related aims for more than 70 years, but there are still key concepts with regard to actinide chemistry that have not been rigorously defined. To name a few, we’ve yet to show consistent control of the way uranium bonds within various chemical systems, thoroughly investigate the coordination chemistry of neptunium as compared with the better-known uranium atom, or demonstrate a complete understanding of the behavior of Np-237 within environmental systems.

The potential for a resurgence of nuclear energy in the United States coupled with a worldwide lack of faith in nuclear matters following the nuclear accident at

Fukushima-Daiichi dictates that the actinide community seek a thorough understanding of the mechanisms that may fuel technological advancement and safeguard against environmental contamination.

1.2 Rationale for Study

The actinide elements represent a frontier of the periodic table with tremendous exploration potential. The elements (notably U, Np and Pu) are of continuing importance for the United States because of their prominent place in nuclear energy production, waste management and environmental remediation, and nonproliferation strategy. Developing advanced energy systems and exploring effective waste management and environmental remediation techniques are core interests for the future in basic energy science research (Office of Science,

Department of Energy, 2008). 3

The actinides are unlike any other group of elements. They are distinguished by their radioactivity, multiple oxidation states and complex crystalline structures.

All fifteen elements in the actinide series are radioactive and have half-lives ranging from fractions of seconds to billions of years. In Table 1.1, isotopes of select actinide elements are listed with their corresponding half-lives. Longer-lived radioisotopes such as U-235, Pu-239 and Np-237 in their mobile oxidation states are concerns as environmental contaminants (Office of Science, Department of Energy, 2007a).

These result from Cold War-era weapons production and the present-day storage of nuclear waste.

TABLE 1.1

ISOTOPES OF SELECT ACTINIDE ELEMENTS WITH HALF-LIVES AND DECAY MODE

(MORSS ET AL., 2006)

Isotope Half-life Decay Mode 230Th 7.538 x 104 yr α 231Th 25.52 h β — 232Th 1.405 x 1010 yr α 234Th 24.10 d β — 233U 1.592 x 105 yr α 234U 2.455 x 105 yr α 235U 7.038 x 108 yr α 238U 4.468 x 109 yr α 235Np 396.1 d EC 236Np 1.54 x 105 yr EC 237Np 2.144 x 106 yr α 239Np 2.2565 d β — 238Pu 87.7 yr α 239Pu 2.411 x 104 yr α 240Pu 6.561 x 103 yr α 244Pu 8.08 x 107 yr α

The radioactivity of the actinide elements is caused by their nuclear instability. In order to become more stable, the nucleus of an actinide element undergoes radioactive decay, releasing gamma rays, alpha particles, beta particles or neutrons. The process of decay produces new daughter elements that may be stable or radioactive. For example, the transformation of U-235 used in nuclear reactors results in the formation of Np-237 through a process of neutron capture, gamma emission and beta decay (Morss et al., 2006).

In natural systems, the oxidation state of an actinide element can greatly impact its environmental fate (Morss et al., 2006). Similar to transition metals, the 5

actinide elements show significant variability with oxidation states ranging from 3+ to 7+ (Figure 1.2). Uranium may be present in oxidation states 3+ through 6+, but the most environmentally relevant oxidation states of uranium are 4+ (insoluble in aqueous systems) and 6+ (soluble in aqueous systems). Neptunium may exist in oxidation states 3+ through 7+. The most environmentally important oxidation state of neptunium under oxidizing conditions is 5+, which is soluble in aqueous systems.

Figure 1.2 Actinide series oxidation states with the environmentally-relevant oxidation states highlighted in green. Those predominant under oxidizing conditions are shown with diagonal lines.

Due to their relative stability and availability, the early actinides—Th, U, Np and Pu, have been shown to interact with various ligands to form intricate minerals and complex synthetic materials (Müller-Buschbaum, 2009; Burns, 2005; Forbes et al., 2008) . Of these in their most environmentally relevant oxidation states, uranium compounds are the most prevalent followed by thorium, neptunium and plutonium.

Burns published a review of more than 300 inorganic U(VI) crystal structures in

2005 (Burns, 2005). Since then more than 100 additional structures have appeared in the scientific literature. Of those for which complete information is readily available, 20 percent are minerals. Approximately 30 thorium minerals are recognized, but there are no neptunium or plutonium minerals because these elements do not occur in Nature today in any appreciable quantities. The number of synthetic actinide compounds has risen rapidly in the last ten years, perhaps as a result of renewed interest in nuclear energy, as well as advancements in synthesis and characterization techniques.

Synthetic actinide crystalline compounds have been produced through both solid state and solution reactions, where solid state refers to those syntheses that do no include a solvent. Solution reaction methods include syntheses performed over a range of temperatures including both room temperature and mild hydrothermal conditions performed at <300 °C. The two methods produced new compounds at similar rates from the late 1950s through the late 1990s; however, significantly more reported compounds have been synthesized through solution methods over the last ten years, attributable to the following research groups: Burns, Albrecht-

Schmitt and Krivovichev. 7

Understanding the crystal chemistry of the radionuclides through the synthesis and study of actinide materials is a key component to developing advanced energy systems and successful environmental remediation strategies

(Office of Science, Department of Energy, 2007b). The complexity of the subsurface and limited understanding of the way that actinides interact within this complex environment have interfered with the development of predictive models of radionuclide behavior (Office of Science, Department of Energy, 2007a). The work herein contributes to the aim of better understanding the actinide elements by investigating the fundamental crystal chemistry of solid-state uranium compounds and developing laboratory conditions under which the migration behavior of neptunium may be studied.

1.3 Overview and Scope

Here I will present a study of (1) the crystal chemistry of inorganic hexavalent uranium germanate compounds and (2) selected inorganic controls that affect Np-237 incorporation in select mineral phases.

This dissertation is composed of 8 chapters. Chapter 1 provides a brief introduction to the actinide elements, including historical context and unique characteristics. The body of the dissertation is arranged as follows:

 Chapter 2 contains descriptions of experimental methods and characterization techniques;

 Chapter 3 is an introduction to U(VI) and an overview of published uranyl germanate and uranyl silicate compounds with comparisons based on crystalline structures;

 Chapter 4 presents the synthesis and crystal structure of an open- framework uranyl germanate compound;

 Chapter 5 presents the syntheses and crystal structures of four isostructural uranyl germanate compounds;

 Chapter 6 presents a novel synthesis of calcite at room temperature in aqueous solution;

 Chapter 7 is an introduction to environmentally-relevant Np(V) and mineral incorporation studies that compare the Np(V) incorporation behavior of mineral phases calcite and gypsum; and

 Chapter 8 suggests future studies in the area of uranium germanate crystal chemistry and neptunium incorporation.

CHAPTER 2:

RESEARCH DESIGN AND METHODS

The materials described herein were produced through inorganic synthesis methods. These include mild hydrothermal and a variety of bench-top techniques.

The materials were characterized using techniques that include X-ray diffraction, spectroscopy, spectrometry and microscopy. The purpose of such rigorous characterization is to develop constraints for understanding the actinyl ion within a specific crystal system. In this chapter, experimental methods relevant to Chapters 4 through 7 are presented. A complete list of experimental trials can be found in

Appendix B.

2.1 Inorganic Synthesis Methods

2.1.1 Hydrothermal Synthesis

Caution! Although depleted uranium was used in these studies, standard precautions for handling radioactive materials should be followed.

Hydrothermal synthesis methods can be used to produce high quality crystals of uranium germanate compounds. Reactions were carried out in 23-mL polytetrafluoroethylene-lined (PTFE, Teflon®) stainless steel acid digestion vessels.

In these vessels, solutions were heated in an oven held at a constant temperature of

220 °C and an unmeasured elevated pressure for up to 7 days.

Hydrothermal synthesis, in the case of uranium germanates, increases the solubility of GeO2 in solution, thereby creating a reaction system that is not possible under ambient conditions. The mechanisms that produce crystalline products within the reaction vessels are not well understood. This lack of understanding makes crystal growth by hydrothermal methods difficult to predict (Fiegelson,

2004).

In this work, although initial solution concentrations, pH, and volume are known, the reaction progression itself is not studied. After a given period of time, the reaction vessel is removed from the oven and allowed to cool. Only then are the crystalline products removed and prepared through filtering and washing for study.

2.1.2 Ambient Synthesis

2.1.2.1 Evaporation

The crystallization of salts by evaporation is considered one of the oldest methods of transforming materials (Fiegelson, 2004). Evaporation relies on the vaporization of a solvent resulting to the precipitation of a solid, crystalline material under favorable conditions.

Evaporation may occur from a single reactant solution or a mixture of multiple reactant solutions. In the case of a mixture, rapid nucleation associated

with the reaction of the solutions can result in the formation of a fine-grained

polycrystalline material that is unsuitable for single crystal studies.

Synthesis of single crystals by evaporation and heat-assisted evaporation

was attempted for each of the minerals in Table 2.1. Variations in concentration and

pH failed to prevent rapid nucleation and subsequent precipitation of

polycrystalline material.

TABLE 2.1

ATTEMPTED MINERAL SYNTHESIS BY EVAPORATION AND DIFFUSION FOR

ACTINIDE INCORPORATION STUDIES

Mineral Name Formula Method Reference Calcite CaCO3 Evap, Diff Henisch, 1988 Cerussite PbCO3 Evap, Diff Henisch, 1988 Witherite BaCO3 Evap Blount, 1974 Strontianite SrCO3 Evap, Diff Blount, 1974 Anhydrite CaSO4 Evap Henisch, 1988 Gypsum CaSO4·2H2O Evap, Diff Henisch, 1988 Anglesite PbSO4 Evap Blount, 1974 Barite BaSO4 Evap Blount, 1974 Celestite SrSO4 Evap, Diff Blount, 1974 Colemanite CaB3O4(OH)3·H2O Evap Wieder/Clawson Patent, 1967 Gowerite CaB6O8(OH)4·3H2O Evap Wieder/Clawson Patent, 1967 Meyerhofferite CaB3O3(OH)5·H2O Evap Wieder/Clawson Patent, 1967 Borax Na2B4O7 Evap Garrett/Rosenbaum, 1958 Kernite Na2B4O6(OH)2·3H2O Evap Morgan Patent, 1961

2.1.2.2 Diffusion

Synthesis in Gel. To slow nucleation and prevent precipitation of a fine- grained polycrystalline material unsuitable for single crystal studies, compounds of four minerals from Table 2.1 were prepared by diffusion of reactant solutions through a silica hydrogel.

Crystal growth in gel has been well documented for compounds of low solubility with success dating into the late 19th century (Henisch, 1996). A silica hydrogel suitable for synthesis by diffusion may be prepared through hydrolysis of tetramethoxysilane (TMOS) (Arend and Connelly 1982; Robert and Lefaucheux

1988). The hydrogel is prepared as a mixture of 10% TMOS and 90% water. The gel sets in approximately 12 hours at room temperature. Once the gel has set firmly, reactant solutions may be layered on top of the gel.

Single crystals of calcite, cerussite, gypsum, and celestite were grown by gel diffusion in glass U-shaped tubes. To employ this method, silica hydrogel is prepared in the base of a glass U-shaped tube resulting in two arms separated by gel. Reactant solutions are layered on top of the gel in each of the arms.

Figure 2.1 Photo of u-shaped glass tube used in hydro-gel synthesis

Crystals of larger than one millimeter in diameter were in a hydrogel with the growth of calcite and gypsum demonstrating the most promise for further studies. However simple the method, difficulties arise in removal of crystals from the gel. In the absence of a solvent to dissolve the gel while leaving the crystals intact, crystals must be removed painstakingly by hand for study. This method is sufficient for studies of individual crystals but can become tedious for bulk studies.

A modification of this method was attempted in an open-ended glass tube to address difficulties associated with crystal harvesting (Figure 2.2). In the absence of two locations for layering reactant solutions, a metal chloride solution containing a necessary reaction component is substituted for water in the hydrolysis of 14

tetramethoxysilane. The gel is prepared in the base of a tube sealed with Parafilm at one end. Once the gel has set, the Parafilm may be removed, and a reactant solution may be layered on top of the gel.

Figure 2.2 Photo of open-ended glass tubes used in hydrogel synthesis shown with 50-mL centrifuge tubes for scale.

Crystals grew at the solution-gel interface and were more readily removed from the system, but complications arose in further studies with the addition of an acidic uranyl nitrate solution. Under this new condition, crystals were observed to grow at the surface and into the gel with a noticeable nucleation density gradient that was highest at the solution-gel interface, becoming less dense downward into the gel.

Synthesis in Solution. Following a method for crystal growth by diffusion in aqueous solution described for the synthesis of sparingly soluble salts (Fernelius

and Detling, 1934), calcite and gypsum were grown to satisfactory size and purity.

The method employs water as a diffusive barrier through which saturated reactant solutions intermingle to form large single crystals in a period of days.

Following exactly the method described by Fernelius and Detling, crystals of gypsum were grown to greater than one millimeter in length. Similar methods were described by Fernelius and Detling for the synthesis of carbonates, but these unsuccessful attempts were attributed by the authors to the insoluble nature of the carbonate minerals.

Modified from the methods of Fernelius and Detling, large crystals of calcite were grown successfully by diffusion through aqueous solution. Crystal growth was achieved by lowering the pH of the diffusive solution. This work is further described in Chapter 6.

2.2 Materials Characterization

Single Crystal X-ray Diffraction. Characterization by single crystal X-ray diffraction results in the development of a structural model based on the arrangement of atoms within a crystalline material (Lin and Lii, 2008; Nguyen et al.,

2011). When an X-ray beam strikes a crystalline material, the beam is diffracted at specific measurable angles and intensities. The emitted X-rays may result in constructive or destructive interference depending on the angle of the incident beam, the direction of the diffracted beam, and the arrangement of atoms within the crystalline material (Massa, 2004).

Bragg’s Law. Constructive interference follows Bragg’s Law, 2dsinθ = nλ, where n is the order of diffraction, λ is the wavelength of the incident X-ray beam, d is the lattice-plane spacing, and θ is the angle of incidence (Massa, 2004). Diffraction occurs when the conditions of Bragg’s Law are met (Figure 2.4).

Figure 2.3 Derivation of the Bragg Equation

The Phase Problem. The process of collecting data for a crystal structure determination yields unit cell parameters, a space group, and intensity data that may be used to locate atoms in the unit cell. A complication to structure solution known as the phase problem arises because experimental measurements only

provide intensity data. Phase information in structure factors is lost and only amplitudes are known (Massa, 2004).

The phase problem is solved by the creation of a structural model that includes well-defined xyz coordinates relative to the origin of a well-defined space group. Given these conditions, theoretical structure factors may be calculated that contain the desired phase information.

Crystal structure solution and refinement for the compounds described in

Chapters 4 and 5 began with the selection of crystals examined under cross- polarized light to observe the presence of extinctions as a way to select a single crystal. A suitable single crystal of a given compound was selected and mounted for single crystal X-ray diffraction studies using a Bruker three-circle single-crystal X- ray diffractometer equipped with either an APEX I or an APEX II CCD detector and

Mo Kα radiation. A sphere of three-dimensional diffraction data was collected at room temperature for each crystal using frame widths of 0.5 ° in ω. If necessary, additional data were collected under a stream of liquid nitrogen gas at 110K using a

Cryo-Industries low-temperature system. Data were integrated and corrected for background, Lorentz, and polarization effects using the APEX II software, and were corrected for absorption empirically using SADABS.

Structures were solved and refined using SHELXTL (Sheldrick, 1996) on the basis of F2. The final refinements included all atomic positional coordinates, anisotropic displacement parameters for U sites, and a mixture of anisotropic and isotropic displacement parameters for the remaining atoms as the data permitted.

Full details of the structures are provided in chapters 4 and 5. 18

TABLE 2.2

PROCEDURE FOR CRYSTAL STRUCTURE DETERMINATION

Procedure Additional Information 1. Crystal synthesis Evaporation, diffusion, hydrothermal 2. Select crystal for analysis 3. Mount and center crystal Glass fiber mount, Cryo-loop mount 4. Collect data / Determine unit cell APEX II 5. Collect diffraction data APEX II 6. Data integration, reduction, correction APEX II 7. Determine space group XPREP 8. Apply absorption correction XPREP or SADABS 9. Solve structure by Direct Methods XS 10. Structure refinement by least XL squares 11. Make atoms anisotropic and add weighting scheme 12. Check for higher symmetry and PLATON / CIFcheck confirm structure 13. Prepare for publication enCIFer 14. Prepare structure images CrystalMaker

Powder X-ray Diffraction. Characterization by power X-ray diffraction

(PXRD) results in a series of peaks with specific intensities that may be used for structure determination (Lin and Lii, 2008; Nguyen et al., 2011). In this work, the technique is used for phase identification in Chapter 6 and to rule out phase transitions under elevated temperatures in Chapters 4 and 5.

Powder X-ray diffraction patterns were collected for selected compounds, as reported in Chapters 4 and 5, and compound residue after heating to 900 °C using a

Scintag θ-θ diffractometer equipped with a solid-state point detector at room temperature over the angular range 5-90° (2θ, Cu Kα) with a step width of 0.05° and

a fixed counting time of 1 s/step. Experimentally derived powder diffraction patterns are compared with patterns calculated for single crystal structures in

Chapters 4 and 5.

Fourier Transform Infrared Microspectroscopy. Infrared (IR) spectroscopy is an absorption spectroscopy method that can be used to identify the presence of various chemical species in a substance (Lin and Lii, 2008; Nguyen et al.,

2011). An IR spectrum was obtained for each compound using a SensIR Technology

IlluminatIR FT-IR microspectrometer equipped with a diamond ATR objective. Each spectrum was taken from 650 to 4000 cm-1 with a beam aperture of 100 µm for crystals that were stored in a desiccator for 24 hours prior to analysis. Infrared spectra are provided for compounds in Chapters 4 and 5.

Ultraviolet-Visible and Near-Infrared Spectroscopy. Absorption spectroscopy measures electronic transitions from the ground state to the excited state. This method can be used to verify the oxidation state of uranium in a crystalline material (Diwu et al., 2010; Unruh et al., 2012). Absorption data were acquired for selected compounds using a Craic Technologies UV—vis—NIR microspectrophotometer. Each spectrum was taken from 250 to 1500 nm.

Absorption spectra are provided in Chapter 5.

Electron Microprobe Analysis. An electron microprobe (EMPA) may be used to determine chemical composition of a solid material (Wang et al., 2002;

Locock and Burns, 2003). Elemental analyses were done for single crystals of compounds reported in Chapter 5 using a Cameca SX50 electron microprobe.

Standards were natural paracelsian (Ba), Ge metal, UO2 (Oak Ridge), and microcline

(K). Quantitative wavelength dispersive analyses were done for U, Ge, K, and Ba.

Thermogravimetric Analysis. Themogravimetric analysis (TGA) measures weight loss of a solid sample under elevated temperatures and can be used to determine structural changes upon heating in conjunction with powder X-ray diffraction studies (Wang et al., 2002; Nguyen et al., 2011). Thermogravimetric measurement was done for selected compounds using a Netzsch TG209 F1 Iris thermal analyzer. Samples were loaded into an Al2O3 crucible and heated from 20 to

900 °C at a rate of 5 °C/min under flowing nitrogen gas. Thermogravimetric data are provided for select compounds in Chapters 4 and 5.

Inductively Coupled Plasma Mass Spectrometry. Inductively coupled plasma mass spectrometry (ICP-MS) may be employed in solution or solid mode to determine elemental or isotopic concentrations (Thakur and Mulholland, 2012;

Reeder et al., 2000). Concentrations of uranium and neptunium were measured in medium resolution for solution samples using a high-resolution magnetic sector

ELEMENT 2 ICP-MS and solid samples by the addition of a 213 nm ND-YAG New

Wave Research Laser Ablation system. The results are provided in Chapter 7.

CHAPTER 3:

STRUCTURAL OVERVIEW OF HEXAVALENT URANIUM GERMANATES AND

SILICATES

Synthesis-based studies of hexavalent uranium crystal chemistry have been extensively explored with regard to phosphates, molybdates and arsenates, yet are non-exhaustive in other areas, including silicates and germanates (Burns, 2005).

The creation of purely inorganic compounds may have value in changing the way that nuclear fuel is currently produced, stored or reprocessed. Beyond this, the systematic production and molecular level study of these synthetic compounds may elucidate properties and trends previously unrealized.

In this chapter, an introduction to hexavalent uranium coordination chemistry is to aid the reader in placing subsequent work on hexavalent uranium germanates and silicates within the broader context.

3.1 Introduction to the Crystal Chemistry of Hexavalent Uranium

Uranium may be present in oxidation states 3+ through 6+, but the most environmentally relevant oxidation states of uranium are 4+ and 6+. The oxidation of insoluble tetravalent uranium to soluble hexavalent uranium has been documented for uraninite in reference to the expected behavior of UO2 during the

lifecycle of a nuclear fuel (Finch and Ewing, 1992; Wronkiewicz et al., 1992, 1996,

1997; Buck et al., 1997; Wronkiewicz and Buck, 1999; Finch et al., 1999).

In its hexavalent state, uranium is typically strongly bonded to two oxygen atoms, producing a nearly linear ionic species, (UO2)2+. The uranyl ion is the axis on which uranyl polyhedra are constructed, as it may be further coordinated about its equatorial plane by four, five, or six ligands to form a square, pentagonal, or hexagonal bipyramidal polyhedron. These polyhedra may arrange themselves into solid materials by the formation of isolated polyhedra and finite clusters or they may link together into extended structures through vertex- or edge-sharing to form chains, sheets, or frameworks. This polyhedral arrangement of strongly-bonded, high-valence cations defines the typically anionic structural unit. Charge is balanced by large, low-valence cations that define the interstitial unit (Hawthorne, 1992,

1994; Schindler and Hawthorne, 2001).

Sheet structures, which result from extensive bonding through equatorial uranyl ligands, are the most prevalent structural configuration within the U(VI) hierarchy (Burns, 2005). Among the least common features are cation—cation interactions (CCIs), which occur when an oxygen atom of one uranyl ion acts also as an equatorial oxygen atom in a neighboring uranium polyhedron (Sullivan et al.,

1961).

Burns’ 2005 hierarchy presents a system of organization for 368 well- resolved crystal structure determinations of hexavalent uranium minerals and inorganic compounds published in the literature at the time. The primary basis of organization is by increasing polymerization of uranium polyhedra where the 23

categories are isolated polyhedra, finite clusters, chains, sheets and frameworks.

Within these categories, structures are gathered with regard to similar structural features. For example, sheet structures in accordance may be grouped by anion topology. The creation of an anion-topology model results in a two-dimensional tiling of space that allows comparison of complex structures that may not have been easily achieved via polyhedral representation (Miller et al., 1996; Burns, 1997,

2005). Similarly, a system of nodes (Fig. 3.1) may be used to illustrate the connectedness of a uranyl polyhedron to adjacent higher-valence polyhedra

(Krivovichev, 2004).

Since 2005, the number of inorganic hexavalent uranium structure solutions has grown to more than 500. The bulk of this growth can be attributed to an increase in hydrothermal synthesis by Alekseev, Krivovichev and Locock (Appendix

C). Through their work, structure solutions of phosphates, arsenates and selenates have seen the most progress. By this method, I have undertaken my own effort, adding to the catalog of hexavalent uranium structures by the synthesis and study of uranyl germanate compounds. An overview of published uranium germanate structures is presented here alongside those of uranyl silicates for comparison.

Those compounds newly synthesized by my efforts are presented in chapters 4 and

3.2 Overview of Germanium and Silicon Occurrence, Coordination and Structures

Germanium (Ge) and silicon (Si) are metalloids in the carbon group of elements containing four electrons each in the outermost electronic shell. Predicted in 1869 by Dmitri Mendeleev, germanium was first known as ekasilicon—a name that disclosed its location one position below silicon on the periodic table of elements. Unlike silicon, the second most abundant element in the Earth’s crust, germanium is considered uncommon, but not rare, with a crustal abundance of 1.6 ppm (Höll et al., 2007).

Germanium is enriched in coal, iron and sulfide deposits, and has been concentrated in quantities as high as 3000 ppm in the zinc sulfide mineral sphalerite

(Bernstein, 1985). The bulk of germanium’s abundance, however, is attributed to trace quantities in silicate minerals. This occurs through isomorphous 25

substitution—a process by which one cation may substitute for another if they have identical charges and similar radii.

Silicon, second only to oxygen in elemental crustal abundance, forms the largest number of compounds with other elements after carbon (Liebau, 1985). The structural configurations of silicate minerals and synthetic compounds have been studied extensively due to their abundance and significance in commercial and industrial application.

Tetrahedral coordination by oxygen is a common feature of both Ge and Si.

The formation of tetrahedra and subsequent linkage into chains and rings leads both germanates and silicates to tend toward extended frameworks. Octahedral coordination is possible for both germanium and silicon at high pressures, and a 5- coordinate GeO5 transitory configuration has been observed (Hannon, 2007;

Pramana et al., 2007). All but one uranyl germanate is of this three-dimensional structure type. Uranyl silicates form frameworks but are better known for the formation of sheets, especially in the uranophane group.

Structural similarity is limited to three uranium germanate compounds with crystalline structures analogous to uranium silicate compounds. These are

(UO2)2(GeO4)(H2O)2 (Legros and Jeannin, 1975a) and the silicate mineral soddyite,

(UO2)2(SiO4)(H2O)2 (Demartin et al., 1992); [Cu(H2O)4](UO2HGeO4)2(H2O)2 (Legros and Jeannin, 1975b) and the silicate mineral cuprosklodowskite,

[Cu(H2O)4](UO2HSiO4)2(H2O)2 (Rosenzweig and Ryan, 1975);

Cs2[(UO2)(Ge2O6)](H2O) (Ling et al., 2010) and RbNa(UO2)(Si2O6)(H2O) (Wang et al.,

2002). 26

Of the more than 500 published inorganic U(VI) structures, there are thirteen

U(VI) germanates and twenty-three U(VI) silicates. Ten U(VI) silicate minerals have been identified, but there are no known U(VI) germanate minerals.

3.3 Structural descriptions of uranyl germanates

3.3.1 Sheets containing isolated tetrahedra

One of two uranium germanate compounds with structures analogous to uranium silicates, [Cu(H2O)4](UO2HGeO4)2(H2O)2 is the lone sheet structure of the uranium germanates (Fig. 3.2a). In this structure, chains of edge-sharing uranyl pentagonal bipyramids are linked by germanate tetrahedra through edge- and vertex-sharing to form sheets of the uranophane-type topology (Legros and Jeannin,

1975b). Charge-balance is provided by Cu2+ in the interlayer. See

Cuprosklodowskite, Cu[(UO2)(SiO3OH)]2(H2O)6.

3.3.2 Frameworks containing isolated tetrahedra

The second of two uranium germanate compounds with structures analogous to uranium silicates, (UO2)2(GeO4)(H2O)2 (Fig. 3.2b) contains chains of edge-sharing uranyl pentagonal bipyramids that are linked through edge-sharing with germanate tetrahedra to form a three-dimensional framework (Legros and

Jeannin, 1975a). This structure is unusual because H2O coordinates the uranyl, which is uncommon in minerals. See Soddyite, (UO2)2(SiO4)(H2O)2.

3.3.3 Frameworks containing dimers of tetrahedra

Two mixed-valence uranium germanate compounds published in 2008,

Rb3(U5+UO4)(Ge2O7) and Cs3(U5+UO4)(Ge2O7) contain both pentavalent and hexavalent uranium (Lin and Lii, 2008). The structures have chains of vertex- sharing uranium polyhedra linked by vertex-sharing with Ge2O7 dimers of tetrahedra (Fig. 3.2c).

Published alongside Rb3(U5+UO4)(Ge2O7) and Cs3(U5+UO4)(Ge2O7) as a minor product of the reaction (Lin and Lii, 2008), Cs6[(UO2)3(Ge2O7)2](H2O)4 has a framework structure containing Ge2O7 dimers of tetrahedra that are linked to uranyl square bipyramids through vertex-sharing to form 12-membered channels (Fig.

3.2d). Cs+ is located within channels that extend through the framework.

One of three uranium germanate compounds published in 2010 (Ling et al.,

2010), Ag[(UO2)2(HGe2O7)](H2O) is formed by chains of edge-sharing uranyl polyhedra linked through edge- and vertex-sharing with HGe2O7 dimers of tetrahedra (Fig. 3.2e).

3.3.4 Frameworks containing chains of tetrahedra

The second of three uranium germanate compounds published in 2010 (Ling et al., 2010), Ag2[(UO2)3(GeO4)2](H2O)2 is a framework structure created by chains of edge-sharing uranyl polyhedra that further share edges and vertices with chains of vertex-sharing GeO5 triangular bipyramids (Fig. 3.2f). Similar GeO5 triangular

bipyramids occur in other germanium compounds but are a divergence from the coordination found in silicate compounds.

Four of the five uranium germanate compounds published in 2011 (Morrison et al., 2011), NH4[(UO6)2(UO2)9(GeO4)(GeO3OH)], K[(UO6)2(UO2)9(GeO4)(GeO3OH)],

Li3O[(UO6)2(UO2)9(GeO4)(GeO3OH)] and Ba[(UO6)2(UO2)9(GeO4)2] are nearly isostructural. The dense framework structures are formed as sheets of pentagonal bipyramidal uranyl polyhedra connected through cation-cation interactions (CCIs) share edges with trimers of pentagonal bipyramid uranium polyhedra canted about chains of GeO5 polyhedra (Fig. 3.2g). The Ba compound contains isolated Ge tetrahedra instead of chains (Fig. 3.2h). Also present, distorted uranium octrahedra share edges with pentagonal bipyramids of uranium in the CCI sheet. These structures are described in further detail in Chapter 5.

3.3.5 Frameworks containing rings of tetrahedra

The third of three uranium germanate compounds published in 2010 (Ling et al., 2010), Cs2[(UO2)(Ge2O6)](H2O) contains germanate tetrahedra that form four- membered rings that link through vertex-sharing with uranyl polyhedra to create a channel-bearing framework structure (Fig. 3.2i). This structure is topologically similar to RbNa(UO2)(Si2O6)(H2O) and is described in further detail in Chapter 4.

The fifth uranium germanate compound published in 2011 (Nguyen et al.,

2011), Cs8U4+(UO2)3(Ge3O9)3(H2O)3 is mixed-valent containing both tetravalent and hexavalent uranium. The structure contains three-membered rings of GeO4

tetrahedra that link by vertex-sharing with uranium polyhedra to form a framework

(Fig. 3.2j).

TABLE 3.1

HEXAVALENT URANIUM GERMANATES

Name Fig. Formula S.G. a (Å) b (Å) c (Å) β (°) Ref.

2a [Cu(H2O)4](UO2HGeO4)2(H2O)2 C2/m 17.660 7.148 6.817 112.8 1 2b (UO2)2(GeO4)(H2O)2 Fddd 8.179 11.515 19.397 2 2c Rb3(U5+UO4)(Ge2O7) P21/n 6.976 12.228 15.399 100.56 3 2c Cs3(U5+UO4)(Ge2O7) P21/n 7.105 12.573 15.561 101.31 3

31 2d Cs6[(UO2)3(Ge2O7)2](H2O)4 P21/n 7.642 10.328 18.854 92.94 3

2e Ag[(UO2)2(HGe2O7)](H2O) Ama2 7.124 10.771 14.024 4 2f Ag2[(UO2)3(GeO4)2](H2O)2 Pnma 10.046 7.470 17.776 4 2g NH4[(UO6)2(UO2)9(GeO4)(GeO3OH)] P3¯ 1c 10.253 10.253 17.397 5 2g K[(UO6)2(UO2)9(GeO4)(GeO3OH)] P3¯ 1c 10.226 10.226 17.150 5 2g Li3O[(UO6)2(UO2)9(GeO4)(GeO3OH)] P3¯ 1c 10.267 10.267 17.056 5 2h Ba[(UO6)2(UO2)9(GeO4)2] P3¯ 1c 10.201 10.201 17.157 5 2i Cs2[(UO2)(Ge2O6)](H2O) P21/n 7.916 21.595 12.466 96.96 4 2j Cs8U4+(UO2)3(Ge3O9)3(H2O)3 P63/m 14.885 14.885 11.032 6 References: (1) Legros and Jeannin, 1975; (2) Legros and Jeannin, 1975; (3) Lin and Lii, 2008; (4) Ling et al., 2010; (5) Morrison et al., 2011; (6) Nguyen et al., 2011.

Figure 3.2 (Continued)

3.4 Structural descriptions of uranyl silicates

3.4.1 Sheets containing isolated tetrahedra: The uranophane-group minerals

The uranophane anion-topology dominates the uranyl silicates. Described in detail by Burns, the uranophane anion-topology is formed by chains of edge-sharing pentagons separated by chains of edge-sharing triangles and squares (Burns, 2005). 34

The simplified anion-topology for uranophane-type silicates, known as uranophane- group minerals, contains pentagons in place of uranyl pentagonal bipyramids, triangles in place of silicate tetrahedra, and squares in place of void-space. Three graphical isomers exist for the uranophane-group minerals: (1) the apical ligands of silicate tetrahedra alternately extend above and below the sheet in uranophane, boltwoodite, cuprosklodowskite, sklodowskite and kasolite; (2) the apical ligands of silicate tetrahedra extend above the sheet in oursinite; and (3) the apical ligands of the silicate tetrahedra alternately extend in pairs above and below the sheet in β- uranophane. While the uranophane-group minerals vary structurally based on the orientation of the apical oxygen atoms of the silicate tetrahedra, the anion-topology, showing only two-dimensional triangles, is the same. The interlayer may contain low-valence cations or H2O (Burns, 2005).

Boltwoodite, (K0.56Na0.42)[(UO2((SiO3OH)](H2O)1.5, was first described in

1956 (Frondel and Ito, 1956). In this structure (Fig. 3.3a), chains of edge-sharing uranyl pentagonal bipyramids are linked by silicate tetrahedra through edge- and vertex-sharing to form sheets of the uranophane anion-topology (Burns, 1998).

Charge balance is provided by K+ and Na+ in the interlayer. Cs-substituted boltwoodite (Burns, 1999), Cs[(UO2)(SiO3OH)]2, contains Cs+ in the interlayer (Fig.

3.3a).

Cuprosklodowskite, Cu[(UO2)(SiO3OH)]2(H2O)6, is formed by chains of edge-sharing uranyl pentagonal bipyramids that are linked by silicate tetrahedra through edge- and vertex-sharing to form sheets of the uranophane-anion topology

(Rosenzweig and Ryan, 1975). Charge balance is provided by Cu2+ in the interlayer 35

(Fig. 3.3a). It is the first of two uranium silicate minerals with a uranyl germanate analogue. Sklodowskite (Ryan and Rosenzweig, 1977), Mg[(UO2)(SiO3OH)]2(H2O)6, contains Mg2+ in the interlayer (Fig. 3.3a). See [Cu(H2O)4](UO2HGeO4)2(H2O)2.

Kasolite, Pb[(UO2)(SiO4)](H2O), is formed by chains of edge-sharing uranyl pentagonal bipyramids that link to silicate tetrahedra through edge- and vertex- sharing to form sheets of the uranophane anion-topology (Ryan and Rosenzweig,

1977). Charge balance is provided by Pb2+ in the interlayer (Fig. 3.3a).

Oursinite, (Co0.8Mg0.2)[(UO2)(SiO3OH)]2(H2O)6, is formed by chains of edge- sharing uranyl pentagonal bipyramids that link to silicate tetrahedra through edge- and vertex-sharing to form sheets of the uranophane type topology (Kubatko and

Burns, 2006). Charge balance is provided by Co2+ and Mg2+ in the interlayer (Fig.

3.3b). Oursinite differs from uranophane, boltwoodite, cuprosklodowskite, sklodowskite and kasolite in the orientation of the apical ligands of the silicate tetrahedra. In oursinite, the apical ligands all extend in the same direction. These differences can be seen in Figure 3.3.

Uranophane (Ginderow, 1988) and β-uranophane (Viswanathan and

Hameit, 1986), Ca[(UO2)(SiO3OH)]2(H2O)5, are members of the uranophane group.

In their structures (Fig. 3.3a and Fig. 3.3c), chains of edge-sharing uranyl pentagonal bipyramids are linked by silicate tetrahedra through edge- and vertex-sharing to form sheets of the uranophane type topology. Charge balance is provided by Ca2+ in the interlayer. Their structures differ in the orientation of the apical ligand of the silicate tetrahedra. These differences can be seen in Figures 3.3a and 3.3c.

3.4.2 Sheets containing rings of tetrahedra

Haiweeite, Ca[(UO2)2Si5O12(OH)2](H2O)3, was first described in 1959. In this structure (Fig. 3.3j), single chains of edge-sharing uranium pentagonal bipyramids are linked into a sheet through edge- and vertex-sharing with a crankshaft-like chain of silicate tetrahedra containing four-membered rings (Burns, 2001).

3.4.3 Frameworks containing isolated tetrahedra

The second of two uranium silicate compounds with structures analogous to uranium germanates (Demartin et al., 1992), soddyite, (UO2)2(SiO4)(H2O)2 contains chains of edge-sharing uranyl pentagonal bipyramids that are linked through edge- sharing with silicate tetrahedra to form a three-dimensional framework (Fig. 3.3d).

See (UO2)2(GeO4)(H2O)2.

3.4.4 Frameworks containing dimers of tetrahedra

The structure of [K3Cs4F][(UO2)3(Si2O7)2] contains vertex-sharing silicate dimers that further vertex-share with uranyl square bipyramids to form sheets.

These sheets link with additional uranyl square bipyramids to form an open framework structure (Fig. 3.3e). The structural elements of

[NaRb6F][(UO2)3(Si2O7)2] relevant to a discussion of silicate polymerization are analogous to [K3Cs4F][(UO2)3(Si2O7)2] (Lee et al., 2009).

3.4.5 Frameworks containing chains of tetrahedra

The Rb2(UO2)(Si2O6)(H2O)0.5 structure (Fig. 3.3f) contains chains of silicate tetrahedra that are linked through vertex-sharing with uranyl square bipyramids to form an open framework (Huang et al., 2003). The structure of

Cs2(UO2)(Si2O6)(H2O)0.5 is analogous.

The Rb4(UO2)2(Si8O20) structure (Huang et al., 2003) contains a “branched double chain” of silicate tetrahedra formed through vertex-sharing (Fig. 3.3g). These chains are linked through vertex-sharing with uranyl square bipyramids to form an open framework.

The K5(UO2)2[Si4O12(OH)] structure (Chen et al., 2005b) contains chains of vertex-sharing silicate tetrahedra linked into an open framework by vertex-sharing with uranyl square bipyramids (Fig. 3.3h).

The Cs2(UO2)(Si2O6) structure (Chen et al., 2005a) contains chains of vertex- sharing silicate tetrahedra linked into an open framework by vertex-sharing with uranyl square bipyramids (Fig. 3.3i).

3.4.6 Frameworks containing rings of tetrahedra

Weeksite, K1.26Ba0.25Co0.12[(UO2)2Si5O13)]H2O, was first described in 1960

(Outerbridge et al, 1960). In this structure (Fig. 3.3k), single chains of edge-sharing uranyl pentagonal bipyramids are linked into a framework through edge- and vertex-sharing with a crankshaft-like chain of silicate tetrahedra containing four- membered rings (Jackson and Burns, 2001). Unlike in the structure of haiweeite, the

sheets in the weeksite structure are linked into a framework through the apical ligand of the silicate tetrahedra.

The KNa3(UO2)2(Si4O10)2(H2O)4 structure (Burns et al., 2000) contains sheets of vertex-sharing silicate tetrahedra that form four- and eight-membered rings (Fig.

3.3l). These sheets are linked by vertex-sharing with uranyl square bipyramids to form a framework. The structure of Na4(UO2)2(Si4O10)2(H2O)4 (Li and Burns, 2001) is analogous to KNa3(UO2)2(Si4O10)2(H2O)4.

The RbNa(UO2)(Si2O6)(H2O) structure (Wang et al., 2002) contains rings of vertex-sharing silicate tetrahedra that form sheets through vertex-sharing with uranyl square bipyramids (Fig. 3.3m). These sheets further link with additional uranyl square bipyramids to form an open framework structure.

The Rb2(UO2)(Si2O6)(H2O) structure (Huang et al., 2003) contains vertex- sharing silicate tetrahedra that form isolated four-membered rings (Fig. 3.3n).

These rings are linked into an open framework by vertex-sharing with uranyl square bipyramids.

The Cs2UO2Si10O22 structure (Liu et al., 2011) contains a double layer of six- membered rings formed by vertex-sharing of silicate tetrahedra (Fig. 3.3o). These layers are further linked into an open framework through vertex-sharing with uranyl square bipyramids.

TABLE 3.2

HEXAVALENT URANYL SILICATES

Name Fig. Formula S.G. a (Å) b (Å) c (Å) β (°) Ref.

Boltwoodite 3a (K0.56Na0.42)[(UO2((SiO3OH)](H2O)1.5 P21/m 7.077 7.060 6.648 104.98 1 3a Cs[(UO2)(SiO3OH)]2 P21/m 7.404 7.077 6.657 104.31 2 Cuprosklod. 3a Cu[(UO2)(SiO3OH)]2(H2O)6 P1¯ 7.052 9.267 6.655 89.84 3 Sklodowskite 3a Mg[(UO2)(SiO3OH)]2(H2O)6 C2/m 17.382 7.047 6.610 105.90 4

40 Kasolite 3a Pb[(UO2)(SiO4)](H2O) P21/c 6.704 6.932 13.252 104.22 5

Oursinite 3b (Co0.8Mg0.2)[(UO2)(SiO3OH)]2(H2O)6 Cmca 7.049 17.550 12.734 6 Uranophane 3a Ca[(UO2)(SiO3OH)]2(H2O)5 P21 15.909 7.002 6.665 97.27 7 β-uranophane 3c Ca[(UO2)(SiO3OH)]2(H2O)5 P21/a 13.966 15.443 6.632 91.38 8 Soddyite 3d (UO2)2(SiO4)(H2O)2 Fddd 8.334 11.212 18.668 9 3e [K3Cs4F][(UO2)3(Si2O7)2] Cmc21 7.810 22.282 14.086 10 3e [NaRb6F][(UO2)3(Si2O7)2] Pnnm 11.143 13.515 7.887 10 3f Rb2(UO2)(Si2O6)(H2O)0.5 Pbca 14.627 15.145 16.645 11 3f Cs2(UO2)(Si2O6)(H2O)0.5 Pbca 15.047 15.463 16.732 11 3g Rb4(UO2)2(Si8O20) P1¯ 6.844 8.314 11.273 88.74 11 3h K5(UO2)2[Si4O12(OH)] Pbcm 13.127 12.264 22.233 12 3i Cs2(UO2)(Si2O6) Ibca 15.137 15.295 16.401 13 Haiweeite 3j Ca[(UO2)2Si5O12(OH)2](H2O)3 Cmcm 7.125 17.937 18.342 14 Weeksite 3k K1.26Ba0.25Co0.12[(UO2)2Si5O13)]H2O Cmmb 14.209 14.248 35.869 15 3l KNa3(UO2)2(Si4O10)2(H2O)4 C2 12.782 13.654 8.268 119.24 16

TABLE 3.2 (CONTINUED)

Name Fig. Formula S.G. a (Å) b (Å) c (Å) β (°) Ref.

3l Na4(UO2)2(Si4O10)2(H2O)4 C2/m 12.770 13.610 8.244 119.25 17 3m RbNa(UO2)(Si2O6)(H2O) P1¯ 7.367 7.869 8.177 18 3n Rb2(UO2)(Si2O6)(H2O) P21/n 7.699 20.974 12.050 97.92 11 3o Cs2UO2Si10O22 P21/c 12.251 8.052 23.380 90.011 19 References: (1) Burns, 1998d; (2) Burns, 1999c; (3) Rosenzweig & Ryan, 1975; (4) Ryan & Rosenzweig, 1977; (5) Rosenzweig & Ryan, 1977a; (6) Kubatko & Burns, 2006); (7) Ginderow, 1988; (8) Viswanathan & Hameit, 1986; (9) Demartin et al., 1992; (10) Lee et al., 2009; (11) Huang et al., 2003; (12) Chen et al., 2005; (13) Chen et al., 2005a; (14) Burns, 2001b; (15) Jackson & Burns, 2001; (16) Burns et al., 2000; (17) Li & Burns, 2001a; (18) Wang et al., 2002; (19) Liu et al., 2011.

Figure 3.3 (Continued)

3.5 Discussion

Unlike the majority of U(VI) compounds, including the silicates, that exhibit a tendency toward sheet structures, U(VI) germanates tend almost exclusively toward a framework structural configuration. The polymerization of germanate polyhedra, relative to the silicates, into dimers, chains and rings creates a structural flexibility that results in the creation of complex frameworks. 45

As seen in Figure 3.3, structures containing isolated tetrahedra are the most common, followed closely by those containing rings of tetrahedra. In both cases, the silicates dominate in what could be viewed as a bimodal distribution of polymerization between isolated tetrahedra and rings. The greater structural difference arises in the extended structures of germanates and silicates. All of the silicates, except for soddyite, containing isolated tetrahedra form sheet structures.

Only one uranyl germanate sheet structure, regardless of tetrahedral polymerization, exists.

When substituted for Si in natural specimens, Ge tends to be enriched in the nesosilicates, inosilicates and phyllosilicates (Bernstein, 1985). The tendency for synthetic hexavalent uranium germanates to polymerize to a higher degree than silicates may be due to the somewhat larger Ge cation. Specific to formation under elevated pressures, this property of germanium gives way to different coordination environments allowing germanium oxides to undergo phase transformations at lower pressures than those of silicon (Bernstein, 1985).

TABLE 3.3

HEXAVALENT URANIUM GERMANATES AND SILICATES BY POLYMERIZATION

Formula Polymerization Germanates Silicates

(K0.56Na0.42)[(UO2((SiO3OH)](H2O)1.5 Cs[(UO2)(SiO3OH)]2 Cu[(UO2)(SiO3OH)]2(H2O)6 [Cu(H2O)4](UO2HGeO4)2(H2O)2 Mg[(UO2)(SiO3OH)]2(H2O)6 (UO2)2(GeO4)(H2O)2 Pb[(UO2)(SiO4)](H2O) Ba[(UO6)2(UO2)9(GeO4)2] (Co0.8Mg0.2)[(UO2)(SiO3OH)]2(H2O)6 α - Ca[(UO2)(SiO3OH)]2(H2O)5 β - Ca[(UO2)(SiO3OH)]2(H2O)5 (UO2)2(SiO4)(H2O)2

5+ Rb3(U UO4)(Ge2O7) 5+ Cs3(U UO4)(Ge2O7) [K3Cs4F][(UO2)3(Si2O7)2] Cs6[(UO2)3(Ge2O7)2](H2O)4 [NaRb6F][(UO2)3(Si2O7)2] Ag[(UO2)2(HGe2O7)](H2O)

Rb2(UO2)(Si2O6)(H2O)0.5 Ag2[(UO2)3(GeO4)2](H2O)2 Cs2(UO2)(Si2O6)(H2O)0.5 NH4[(UO6)2(UO2)9(GeO4)(GeO3OH)] Rb4(UO2)2(Si8O20) Li3O[(UO6)2(UO2)9(GeO4)(GeO3OH)] K5(UO2)2[Si4O12(OH)] K[(UO6)2(UO2)9(GeO4)(GeO3OH)] Cs2(UO2)(Si2O6)

Ca[(UO2)2Si5O12(OH)2](H2O)3 K1.26Ba0.25Co0.12[(UO2)2Si5O13)]H2O KNa3(UO2)2(Si4O10)2(H2O)4 Cs2[(UO2)(Ge2O6)](H2O) 4+ Na4(UO2)2(Si4O10)2(H2O)4 Cs8U (UO2)3(Ge3O9)3(H2O)3 RbNa(UO2)(Si2O6)(H2O) Rb2(UO2)(Si2O6)(H2O) Cs2UO2Si10O22

CHAPTER 4:

SYNTHESES, STRUCTURES, AND CHARACTERIZATION OF AN OPEN-

FRAMEWORK URANYL GERMANATE

The following is adapted from Ling, J., Morrison, JM., Ward, M., Poinsatte-Jones, K. and Burns, PC. Inorg. Chem. 2010, 49, 7123-7128.

Uranium is the fuel of commercial nuclear energy and is a problematic environmental contaminant at U mine and mill sites as well as various facilities involved in the cold-war era buildup of nuclear weapons. Hexavalent U, the water- soluble oxidation state, forms the linear (UO2)2+ uranyl ion in most solids and coordination complexes. The crystal chemistry of the uranyl ion is diverse, in part, because it commonly occurs in square, pentagonal, or hexagonal bipyramidal coordination (Burns, 2005; Burns et al., 1997). In inorganic systems the equatorial ligands of these bipyramids are usually O, OH, or H2O, and linkage of uranyl polyhedra with other uranyl polyhedra or other oxyanions is common. As only the equatorial ligands are usually involved in such linkages, sheets of polyhedra dominate. Only ∼15% of inorganic uranyl compounds possess framework structures, although this class of compounds is expanding as new modes of polyhedral connectivity are identified.

Uranyl germanates are of particular interest to us because germanates are known to form a variety of framework structures in different chemical systems

(Beitone et al., 2002; Bu et al., 2000; Cascales, et al. 1998; Conradsson et al, 2000; Li et al., 1998; Medina et al, 2001; O’Keeffe and Yaghi, 1999). In contrast with Si, which is tetrahedrally coordinated in oxide structures other than under extremely high pressures, Ge exhibits GeO4 tetrahedra, GeO5 trigonal bipyramids, and GeO6 octahedra owing to its larger atomic radius. Ge-O bond lengths are longer than Si-O bond lengths (1.76 versus 1.61 Å ) and the Ge-O-Ge angles are typically more acute than Si-O-Si angles (O’Keeffe and Yaghi, 1999). The flexible coordination geometries of Ge foster the formation of open-framework structures with extra-large pores, such as FDU-4 (Zhou et al., 2001) and ASU-16 (Plevert et al., 2001) that contain channels bounded by 24-membered rings.

In order to diversify the range of uranyl-based compounds that possess framework structures, we are exploring the synthesis of uranyl germanates under mild hydrothermal conditions. Here we report the synthesis, structure, and characterization of a novel uranyl germanate framework material.

4.1 Experimental Section

Synthesis. UO2(C2H3O2)2H2O (MV Laboratories, lot no. P705UA1), GeO2

(99.9%, Aldrich), and CsOH (99.9%, Aldrich) were used as received without further purification. Distilled and Millipore filtered water with a resistance of 18.2 MΩ was used in all reactions. Caution! While the UO2(C2H3O2)2H2O used here contains depleted U, standard precautions for handling radioactive materials should be 49

followed. CsOH was chosen arbitrarily to provide a charge balancing cation as a part of a larger combinatorial synthesis plan.

Cs2[(UO2)(Ge2O6)](H2O) was synthesized by loading 1.65 mL of a 4.24 M aqueous CsOH solution (7 mmol), 0.108 g UO2(C2H3O2)2H2O (0.29 mmol), 0.443 g

GeO2 (4.24 mmol), and 2.7 mL of deionized water into a 23 mL Teflon-lined Parr reaction vessel that was sealed and heated at 220 °C for 7 days. After cooling, the product was washed with deionized water and allowed to dry in air. The synthesis gave a pure product consisting of bright-yellow needle-shaped crystals with a yield of 62.5% based on U. Energy dispersive analysis provided a Cs:U:Ge ratio of 2:1:2

(39:20:41%).

Crystallographic Studies. A single crystal was selected using a polarized- light stereomicroscope and was mounted on tapered glass fibers with epoxy for X- ray diffraction analysis. A sphere of diffraction data was collected at 110 K using a

Bruker three-circle X-ray diffractometer equipped with an APEX CCD detector. The data were collected using monochromatic Mo Kα radiation with a frame width of

0.3° in ω and a counting time per frame of 10 s. Unit-cell parameters were refined by least-squares techniques using the Bruker SMART software (Bruker, 1998a). The

SAINT software (Bruker, 1998b) was used for data integration including Lorentz, background, and polarization corrections. An empirical absorption correction was applied using the program SADABS. The SHELXTL version 5 series of programs was used for the solution and refinement of the crystal structures. Selected data collection parameters and crystallographic information are listed in Table 4.1.

Selected bond distances are listed in Table 4.2. 50

TABLE 4.1

CRYSTALLOGRAPHIC DATA FOR Cs2[(UO2)(Ge2O6)](H2O)

Formula Cs2[(UO2)(Ge2O6)](H2O) Formula Mass 793.03

Crystal system Monoclinic

Space group P21/n a (Å) 7.9159(2) b (Å) 21.5949(5) c (Å) 12.4659(3) β (°) 96.964(1) V (Å3) 2115.24(9) Z 8

 (Å) 0.71073 µ (mm-1) 27.727

 (°) maximum 25.25

calcd (g cm–3) 4.980 goodness-of-fit on F2 0.863

R(F) for Fo2 > 2(Fo2) a 0.0360

Rw(Fo2) b 0.0694

Note 1 R: conventional residue, calculated from Fo-data; Rw: weighted residual, calculated 2 2 2 2 4 1/2 from Fo-data; a: R(F)=Σ||Fo|-|Fc||/Σ|Fo|; b: Rw(Fo )=[Σ[w(Fo - Fc ) ]/ΣwFo ] .

TABLE 4.2

SELECTED BOND LENGTHS (Å) FOR Cs2[(UO2)(Ge2O6)](H2O)

U(1)–O(1) 1.820(8) Ge(1)–O(4) 1.718(8)

U(1)–O(2) 1.828(7) Ge(1)–O(8) 1.741(8)

U(1)–O(3) 2.204(8) Ge(1)–O(13) 1.751(7)

U(1)–O(4) 2.231(9) Ge(1)–O(14) 1.737(8)

U(1)–O(5) 2.264(8) Ge(2)–O(6) 1.732(8)

U(1)–O(6) 2.223(8) Ge(2)–O(9) 1.739(8)

U(2)–O(7) X 2 1.817(7) Ge(2)–O(14) 1.757(8)

U(2)–O(8) X 2 2.219(8) Ge(2)–O(15) 1.779(7)

U(2)–O(9) X 2 2.256(8) Ge(3)–O(3) 1.748(8)

U(3)–O(10) X 2 1.809(8) Ge(3)–O(12) 1.708(8)

U(3)–O(11) X 2 2.243(7) Ge(3)–O(15) 1.762(7)

U(3)–O(12) X 2 2.239(8) Ge(3)–O(16) 1.757(8)

Ge(4)–O(5) 1.730(8)

Ge(4)–O(11) 1.732(8)

Ge(4)–O(13) 1.784(7)

Ge(4)–O(16) 1.761(8)

Infrared Spectroscopy. An Infrared spectrum was obtained for a single crystal using a SensIR technology IlluminatIR FT-IR microspectrometer. A single crystal was placed on a glass slide, and the spectrum was collected with a diamond

ATR objective. The spectrum was taken over the range of 650 to 4000 cm-1 with a beam aperture of 100 μm. The spectrum is shown in Figure 4.1.

Thermal Gravimetric Analysis (TGA). A TGA measurement was conducted using a Netzsch TG209 F1 Iris thermal analyzer for 28 mg of powdered material in an Al2O3 crucible that was heated from 20 to 900 °C at a rate of 5 °C/min under flowing nitrogen gas. The data are shown in Figure 4.2.

100

CsUGe1

98 Weight Percentage (%) WeightPercentage

97 0 100 200 300 400 500 600 700 800 900 Temperature (Celsius)

Figure 4.2 Thermal gravimetric profile for Cs2[(UO2)(Ge2O6)](H2O)

Powder X-ray Diffraction. Powder X-ray diffraction patterns of the material and its residue after heating to 900 °C were collected using a Scintag θ-θ diffractometer equipped with a solid-state point detector at room temperature over the angular range 5-90° (2θ, Cu Kα) with a step width of 0.05° and a fixed counting 54

time of 1 s/step. The experimentally derived diffraction patterns are compared with a pattern calculated for the single-crystal structure in Figure 4.3.

Figure 4.3 Powder X-ray diffraction patterns for Cs2[(UO2)(Ge2O6)](H2O), its TGA residue after heating to 900ºC and the simulated pattern from the single-crystal structure.

Bond-Valence Analysis. Bond-valence sums were calculated for U6+—O ,

Ge4+—O and Cs+—O interactions following the bond-valence method (Burns et al.,

1997; Brown and Altermatt, 1985) and are listed in Table 4.3. The calculated sums are in agreement with theoretical valences.

TABLE 4.3

BOND VALENCE SUMS FOR Cs2[(UO2)(Ge2O6)](H2O)

U1 U2 U3 Ge1 Ge2 Ge3 Ge4 Cs1 Cs2 Cs3 Cs4 ∑ O1 0.77 1.02 0.12 1.91

0.77 O2 0.99 0.91 0.11 2.01

O3 1.03 0.98 0.13 2.14 56

O4 0.76 1.08 0.09 1.93

O5 0.73 1.03 0.10 1.86

0.73

O6 0.76 1.02 0.07 1.85

O7 0.92 0.96 0.06 1.94

O8 0.98 0.97 0.17 2.12

O9 0.74 1.11 0.12 1.97

0.74

TABLE 4.3 (CONTINUED)

U1 U2 U3 Ge1 Ge2 Ge3 Ge4 Cs1 Cs2 Cs3 Cs4 ∑

O10 0.79 1.00 0.04 0.16 1.99 O11 0.74 1.04 0.08 0.13 1.99

0.74

O12 0.71 1.05 0.07 0.06 0.09 1.98 max

O13imu 1.58 0.13 0.09 0.24 2.04 n

O14 1.56 0.12 0.14 1.82

57 O15

1.59 0.15 0.11 1.85

1.59 O16 1.61 0.13 0.12 0.17 2.03

1.61 O17 0.16 0.14 0.08 0.38 H2O O18 0.20 0.15 0.35 H2O

∑ 6.16 6.18 6.18 4.12 3.95 4.05 3.97 0.93 0.91 0.94 0.95

Fluorescence Spectroscopy. Fluorescence data were acquired for a single crystal using a Craic Technologies UV-vis-NIR microspectrophotometer with a fluorescence attachment. Excitation was achieved using 365 nm light from a mercury lamp. The fluorescence spectrum is provided in the Figure 4.4.

35000

AgUGe1 AgUGe2 30000 CsUGe1

25000

20000

Intensity 15000

10000

5000

0 350 400 450 500 550 600 650 700 750 800 Wavelength (nm)

4.2 Results

Structure Description. The structure contains three crystallographically unique U6+ cations that are present as approximately linear (UO2)2+ uranyl ions, with

U—OUr (Ur: uranyl) bond lengths ranging from 1.809(8) to 1.828(7) Å . Each of the uranyl ions is coordinated by four ligands that are arranged at the equatorial positions of square bipyramids that are capped by the O atoms of the uranyl ions.

The equatorial ligands are all O atoms of germanate tetrahedra, and equatorial bond lengths (U—Oeq) (eq: equatorial) vary from 2.204(8) to 2.264(8) Å. These U—O bond distances are consistent with the average U—OUr and U-Oeq bond lengths of

1.82(5) and 2.26(6) Å for 54 uranyl square bipyramids in 47 well-refined structures

(Burns, 2005). The four symmetrically distinct Ge4+ cations are tetrahedrally coordinated by O atoms, with Ge—O bond distances ranging from 1.708(8) to

1.784(7) Å.

In the structure of Cs2[(UO2)(Ge2O6)](H2O), four GeO4 tetrahedra share bridging O atoms to create a four-membered Ge4O10 ring (Figure 4.5). Within this ring, Ge—O—Ge angles of the bridges range from 126.0(4) to 132.3(5) , consistent with the average Ge—O—Ge angle of 130 (O’Keeffe and Yaghi, 1999). Each Ge4O10 ring is bridged along [100] through two uranyl square bipyramids that share an equatorial vertex with each of two adjacent Ge4O10 rings. This linkage creates a chain that extends along [100]. The chain is decorated on each side by additional uranyl square bipyramids that share equatorial vertices with two GeO4 tetrahedra that are adjacent in the Ge4O10 ring. As a result, each GeO4 tetrahedron in the ring shares two of its vertices with other tetrahedra, and the other two with square 59

bipyramids. Each square bipyramid shares all four of its equatorial vertices with

Ge4O10 rings, resulting in a framework with composition [(UO2)(Ge2O6)]2- (Figure

4.6). Cs+ cations and H2O molecules are located in channels that are bounded by 10- membered rings consisting of four uranyl bipyramids and six germanate tetrahedra.

Channels extend along [100] with dimensions of 5.2 by 5.4 Å as measured from the centers of O atoms on either side.

Spectroscopy, Thermal Analysis. Sharp bands occurring at 812 and 884 cm-1 are assigned as asymmetric stretches of the uranyl units (Cejka, 1999). Strong bands at 731 and 768 cm-1 are attributed to the asymmetric stretching vibrations of

Ge—O bonds (Paquesledent, 1976). A broad band in the range of 3000-3500 cm-1 and several weak bands centered at 1600 cm-1 are associated with O—H vibrations of the water molecules.

The fluorescence spectrum exhibits several characteristic peaks related to coupling between charge-transfer transitions and uranyl-stretching and -bending 61

modes (Denning et al., 1980). One band at 520 nm and four bands at 534, 545, 570, and 598 nm correspond to electronic transmissions S11  S00 and S10  S0v with v =

0—4, respectively. Compared to the spectrum of UO2(NO3)26H2O, it displays a red shift of about 30 nm that may be due to the difference in coordination environments about the U cations, the hydration level, and the crystal packing (Valeur, 2002).

The thermal data collected reveals a simple one-step 2.42% weight loss over the temperature range 80-200 C (Figure 4.1). This weight loss corresponds to the exit of the H2O groups located within the channels of the framework structure and is in good agreement with the 2.27% expected weight loss based on the crystallographically derived formula. Following dehydration, the uranyl germanate framework persists at least to 900 C. The powder diffraction pattern of the residue after heating to 900 C is very similar to that of the unheated sample, indicating the uranyl germanate framework remained intact (Figure 4.2).

4.3 Discussion

The compound has a novel framework structure consisting of uranyl square and pentagonal bipyramids as well as GeO4 tetrahedra. Polymerization of germanate polyhedra in this structure gives four-membered rings.

The uranyl germanate framework reported here is topologically identical to that of the uranyl silicate RbNa[(UO2)(Si2O6)](H2O) (Wang et al., 2002), but it is the first uranyl compound with a four-membered ring of germanate tetrahedra. This framework is stable to at least 900 C in the case of the germanate compound, in contrast to the silicate compound ,which collapses at about 700 C (Lin et al., 2008). 62

It is apparent that the structures of uranyl germanates tend toward frameworks, whereas those of uranyl silicates in nature are most commonly built from uranyl silicate sheets, as described in the previous chapter. However, hydrothermal syntheses giving uranyl silicates framework structures that display similar connectivities to uranyl germanates have been reported in some cases

(Valeur, 2002).

CHAPTER 5:

U(VI) URANYL CATION-CATION INTERACTIONS IN FRAMEWORK

GERMANATES

The following is adapted from Morrison, JM, Moore-Shay, LJ and Burns, PC. Inorg. Chem. 2011, 50, 2272-2277.

The (UO2)2+ uranyl ion is central to the complex chemistry of U(VI) (Morss et al., 2006). Recent studies have provided unexpected results that challenge our understanding of this normally unreactive functional group (Arnold et al., 2008;

Boncella, 2008; Evans et al., 2005; Fox et al., 2008; Hayton et al., 2005). Of particular interest in the current study is the occurrence of U(VI) uranyl cation-cation interactions (Alekseev et al., 2009; Alekseev et al., 2006; Alekseev et al., 2007;

Krivovichev, 2007; Sullens et al., 2004; Kubatko and Burns, 2006). First found in solutions containing uranyl and neptunyl (Sullivan et al., 1961), a cation-cation interaction occurs where an O atom of one actinyl ion is also an equatorial ligand of a bipyramid about a second actinyl ion. Put another way, one actinyl ion coordinates one or two other actinyl ions. Such interactions provide novel linkages within structural units.

Cation-cation interactions only occur in 2% of U(VI) compounds (Burns,

2005). They are much more common in Np(V) neptunyl compounds and U(V)

compounds, both of which have been the focus of considerable recent attention

(Forbes and Burns, 2007; Forbes et al., 2006; Grigoriev et al., 1988; Grigoriev et al.,

1989; Forbes et al, 2008; Krot and Grigoriev, 2004; Fortier and Hayton, 2010;

Mougel et al., 2009; Arnold et al., 2009; Graves and Kiplinger, 2009; Nocton et al.,

2008). Np(V) neptunyl cation-cation interactions result in a variety of framework structures, as well as a few sheets and chains (Forbes et al., 2008). The few inorganic U(VI) compounds with cation-cation interactions all adopt framework structures, and creation of cation-cation interactions in U(VI) compounds may increase the dimensionality of the structures.

U(VI) uranyl cation-cation interactions affect the structural topologies and properties of actinide materials. On the basis of the handful of known structures, inclusion of cation-cation interactions results in unique structure connectivities.

Here, the uranyl-germanate system is examined because, by analogy with uranyl silicates, uranyl germanates are expected to present considerable structural diversity. The structures of nine U germanate compounds described in Chapter 3 present the expected complexity (Lin et al., 2009; Lin and Lii, 2008; Lin et al., 2008;

Legros and Jeannin, 1975a; Legros and Jeannin, 1975b). One contains U(V), two are mixed-valence U(V)-U(VI) compounds, and in six all of the U is U(VI). With the exception of one that contains structural sheets, each has a complex framework structure.

Four uranyl germanates that were obtained under mild hydrothermal conditions are reported here: NH4[(UO6)2(UO2)9(GeO4)(GeO3(OH))] (1),

K[(UO6)2(UO2)9(GeO4)(GeO3(OH))] (2), Li3O[(UO6)2(UO2)9(GeO4)(GeO3(OH))] (3), 65

and Ba[(UO6)2(UO2)9(GeO4)2] (4). Each presents a complex framework that includes cation-cation interactions.

5.1 Experimental Section

Synthesis. Crystals of compounds 1-4 were synthesized by heating solutions consisting of aqueous uranyl nitrate, GeO2, and the corresponding base. Caution!

Although depleted uranium was used in these studies, standard precautions for handling radioactive materials should be followed. Solutions were heated at 220 °C for 7 days in 23 mL Teflon-lined stainless steel reaction vessels placed in preheated mechanical convection ovens. Products were recovered by filtration and in each case consisted of deep red-orange stacks of pseudo-hexagonal platy crystals ranging in diameter to 500 μm, as well as a fine-grained yellow powder consisting of

UO3(H2O)0.8 and (UO2)2(GeO4)2H2O, verified by powder X-ray diffraction.

Optimization of solution pH and Ge:U ratios provided an increased yield of crystals relative to the microcrystalline phases, but a pure yield was not obtained.

1: 0.675 mL of 2 M aqueous uranyl acetate, 0.675 mL of an aqueous-powder slurry containing 0.010 g of GeO2 powder, 0.413 mL of 4.24 M aqueous NH4OH.

2: 1.35 mL of 2 M aqueous uranyl nitrate, 1.35 mL of an aqueous-powder slurry contqaining 0.020 g of GeO2 powder, 0.825 mL of 4.24 M aqueous KOH.

3: 1.35 mL of 1 M aqueous uranyl nitrate, 1.35 mL of an aqueous- powder slurry containing 0.020 g of GeO2 powder, 0.825 mL of 4.24 M aqueous LiOH.

4: 0.675 mL of 0.2 M aqueous uranyl nitrate, 0.675 mL of an aqueous-powder slurry containing 0.010 g of GeO2 powder, 0.413 mL of 0.25 M aqueous Ba(OH)2.

Single Crystal X-ray Diffraction. Crystals were examined under cross- polarized light, and suitable single crystals of each compound that showed no twinning were selected. These were mounted on a glass fiber for single crystal X-ray diffraction studies using a Bruker three-circle single-crystal X-ray diffractometer equipped with an APEX II CCD detector and Mo Kα radiation. A sphere of three- dimensional diffraction data was collected at room temperature for each crystal using frame widths of 0.5° in ω. Data were integrated and corrected for background,

Lorentz, and polarization effects using the APEX II software, and were corrected for absorption empirically using SADABS. Additional data was collected for a crystal of each compound at 110 K. The crystallographic parameters and refined structure parameters reported in the tables are from the room-temperature data.

Structures were solved and refined using SHELXTL (Sheldrick, 1996) on the basis of F2. Systematic absences of reflections indicated that a c glide is the only translational symmetry operator present. Structures were solved and refined in the space groups P3¯ 1c, C2/c, Cc, and P1, although the unit cell is metrically trigonal.

Merging R factors for all of the data sets ranged from 4.7 to 9.9%, being fairly high because the crystals diffract weakly because of their size. Merging R factors for the monoclinic space groups were only slightly lower than those of P3¯ 1c. As discussed below, each structure model included positional disorder of some sites. Such disorder was required even in the lower symmetry space groups, including P1, so P3¯

1c was selected for final refinements. The final refinement in each case included all atomic positional coordinates, anisotropic displacement parameters for U sites, and a mixture of anisotropic and isotropic displacement parameters for the remaining atoms as the data permitted. Refined anisotropic displacement parameters for the

Ge sites in compounds 1-3 were highly elongated, and a split-site model was subsequently adopted. The corresponding Ge(1) and Ge(2) sites refined to a separation of ∼0.7 Å, only one of which is occupied locally. Data was recollected at

110 K for each compound. However, this did not alleviate the disorder evidenced by the elongated displacement parameters. Selected crystallographic information is given in Table 5.1, and interatomic separations are provided in Table 5.2.

TABLE 5.1

SELECTED CRYSTALLOGRAPHIC PARAMETERS FOR COMPOUNDS 1-4

[1] [2] [3] [4] NH (UO ) (UO ) K(UO ) (UO ) Li O(UO ) (UO ) Ba(UO ) (UO ) structure formula 4 6 2 2 9 6 2 2 9 3 6 2 2 9 6 2 2 9 (GeO4)(GeO3(OH)) (GeO4)(GeO3(OH)) (GeO4)(GeO3(OH)) (GeO4)2

69 formula weight 3385.52 3410.61 3408.33 3508.85 temperature (K) 296(2) 296(2) 296(2) 296(2) wavelength (Å) 0.71073 0.71073 0.71073 0.71073 crystal system trigonal trigonal trigonal trigonal space group P3¯ 1c (No. 163) P3¯ 1c (No. 163) P3¯ 1c (No. 163) P3¯ 1c (No. 163) a (Å) 10.2525(5) 10.226(4) 10.2668(5) 10.2012(5) b (Å) 10.2525(5) 10.226(4) 10.2668(5) 10.2012(5) c (Å) 17.3972(13) 17.150(9) 17.0558(11) 17.1570(12) volume (Å3) 1583.69(16) 1553.1(12) 1556.94(15) 1546.23(15) Z 2 2 2 2 density (g/cm3) 7.100 7.293 7.270 7.537 µ (mm-1) 58.006 59.282 59.005 60.657 F(000) 2774 2798 2794 2872

TABLE 5.1 (CONTINUED)

[1] [2] [3] [4] 0.035 x 0.017 x 0.045 x 0.034 x 0.066 x 0.038 x crystal size (mm) 0.029 x 0.012 x 0.005 0.006 0.007 0.005 theta range for data 2.29 to 27.56 2.30 to 27.69 2.29 to 27.57 2.31 to 27.58 collection (deg) -13<=h<=13, -13<=h<=13, -12<=h<=13, -13<=h<=13, limiting indices -13<=k<=13, -13<=k<=13, -13<=k<=13, -13<=k<=13, -22<=l<=22 -22<=l<=22 -21<=l<=22 -22<=l<=22 reflections 17559 / 1237 17590 / 1229 16252 / 1211 17102 / 1197

70 collected/unique [R(int) = 0.0843] [R(int) = 0.0781] [R(int) = 0.0606] [R(int) = 0.0740]

Full-matrix least-squares on Full-matrix least- Full-matrix least- Full-matrix least- refinement method F2 squares on F2 squares on F2 squares on F2 data/restraints/parameters 1237/0/83 1229/0/83 1211/1/86 1197/0/78

goodness-of-fit on F2 1.199 1.006 1.201 1.148 final R indices R1 = 0.0349 R1 = 0.0232 R1 = 0.0236 R1 = 0.0267 [I > 2σ(I)] wR2 = 0.0960 wR2 = 0.0561 wR2 = 0.0521 wR2 = 0.0745 R1 = 0.0383, R1 = 0.0307, R1 = 0.0287, R1 = 0.0312, R indices (all data) wR2 = 0.0977 wR2 = 0.0593 wR2 = 0.0536 wR2 = 0.0766 largest diff. peak and hole 3.207 and -2.570 1.446 and -2.943 1.133 and -4.073 2.029 and -3.612 (Å)

TABLE 5.2

SELECTED INTERATOMIC DISTANCES (Å) FOR COMPOUNDS 1-4

UGeAmm_10 [1] UGeK_30 [2] UGeLi_29 [3] UGeBa_7 [4] NH4(UO6)2(UO2)9 K(UO6)2(UO2)9 Li3O(UO6)2(UO2)9 Ba(UO6)2(UO2)9 (GeO4)(GeO3(OH)) (GeO4)(GeO3(OH)) (GeO4)(GeO3(OH)) (GeO4)2 U(1)-O(3) 2.060(9) U(1)-O(3) 2.037(6) U(1)-O(3)a 2.053(6) U(1)-O(3)a 2.041(7) U(1)-O(3)a 2.060(9) U(1)-O(3)a 2.037(6) U(1)-O(3)b 2.053(6) U(1)-O(3)b 2.041(7) U(1)-O(3)b 2.060(9) U(1)-O(3)b 2.037(6) U(1)-O(3) 2.053(6) U(1)-O(3) 2.041(7) U(1)-O(4) 2.096(8) U(1)-O(4)b 2.095(6) U(1)-O(4)b 2.118(6) U(1)-O(4)a 2.109(7) U(1)-O(4)b 2.096(8) U(1)-O(4)a 2.095(6) U(1)-O(4) 2.118(6) U(1)-O(4)b 2.109(7) U(1)-O(4)a 2.096(8) U(1)-O(4) 2.095(6) U(1)-O(4)a 2.118(6) U(1)-O(4) 2.109(7) 71 U(2)-O(2) 1.763(10) U(2)-O(2) 1.760(7) U(2)-O(2) 1.772(6) U(2)-O(2) 1.788(7) U(2)-O(5)c 1.828(10) U(2)-O(5)c 1.822(7) U(2)-O(5)c 1.833(6) U(2)-O(5)c 1.843(7) U(2)-O(1)d 2.277(9) U(2)-O(1)d 2.263(6) U(2)-O(1)d 2.255(6) U(2)-O(1)c 2.238(7) U(2)-O(4)e 2.324(8) U(2)-O(4)e 2.294(6) U(2)-O(4)e 2.305(6) U(2)-O(4)d 2.299(7) U(2)-O(4)f 2.339(8) U(2)-O(4)s 2.333(6) U(2)-O(4)f 2.327(6) U(2)-O(4)cc 2.329(7) U(2)-O(5)e 2.428(9) U(2)-O(5)e 2.430(6) U(2)-O(5)e 2.418(6) U(2)-O(5)e 2.416(7) U(2)-O(3)c 2.492(9) U(2)-O(3)c 2.479(7) U(2)-O(3)c 2.472(6) U(2)-O(3)c 2.483(7)

U(3)-O(7) 1.748(10) U(3)-O(7)f 1.751(7) U(3)-O(7) 1.773(6) U(3)-O(6)f 1.771(7) U(3)-O(7)g 1.748(10) U(3)-O(7) 1.751(7) U(3)-O(7)g 1.773(6) U(3)-O(6) 1.771(7)

TABLE 5.2 (CONTINUED)

Ge(1)-O(6) 1.735(5) Ge(1)-O(6) 1.744(7) Ge(1)-O(1)i 1.743(6) Ge(1)-O(1)b 1.711(8) Ge(1)-O(1)l 1.777(9) Ge(1)-O(1)a 1.750(7) Ge(1)-O(1)j 1.743(6) Ge(1)-O(1)j 1.711(7)

Ge(1)-O(1)m 1.777(9) Ge(1)-O(1)a 1.750(7) Ge(1)-O(1)k 1.743(6) Ge(1)-O(1)s 1.711(7) 72

Ge(1)-O(1)n 1.777(9) Ge(1)-O(1)a 1.750(7) Ge(1)-O(6) 1.747(3) Ge(1)-O(7) 1.939(15)

Ge(2)-O(1)l 1.709(9) Ge(2)-O(1)a 1.694(6) Ge(2)-O(1)a 1.718(6) Ge(2)-O(7) 1.569(15) Ge(2)-O(1)m 1.710(9) Ge(2)-O(1)a 1.694(6) Ge(2)-O(1)a 1.718(6) Ge(2)-O(1)b 1.804(9) Ge(2)-O(1)n 1.710(9) Ge(2)-O(1)a 1.694(6) Ge(2)-O(1)a 1.718(6) Ge(2)-O(1)j 1.804(9) Ge(2)-O(8)o 1.881(7) Ge(2)-O(8)a 1.93(2) Ge(2)-O(8)a 1.767(11) Ge(2)-O(1)s 1.804(9) Note 2 Symmetry transformations used to generate equivalent atoms: a: x-1, y, z; b: x+1, y, z; c: -x, -y+1, -z+1; d: -y+1, x-y+1, z; e: -x+y, -x, z; f: x- y+1, x, -z+1; g: -y+1, -x, -z+3/2; h: -x+1, -y, -z+1; i: -y, x-y-1, z; j: -y+1, x-y, z; k: y, -x+y+1, -z+1; l: -x+y+1, -x+1, z; m: x-y-1, x-1, -z+1; n: -x, -y, -z; o: y+1, x+1, z+1/2; p: -x, -y, -z+1; q: y, x, z+1/2; r: y+1, x, z+1/2; s: -x+y, -x+1, z; t: y-1, x-1, z-1/2; u: x-y, -y+1, z-1/2; v: x, x-y, - z+3/2; w: -x+1, -x+y, z-1/2; x: -y+1, -x+1, -z+3/2; y: -y, x-y, z; z: -x+y, y, -z+3/2; aa: x, x-y+1, -z+3/2; bb: -y, -x+1, -z+3/2; cc: -x+2, -y+1, - z+1; dd: -y+1, x-y-1, z; ee: x-y, x-1, -z+1; ff: -y+1, -x+1, -z+1/2; gg: -x+y+2, -x+1, z; hh: -x+2, -y, -z+1; ii: x, x-y-1, -z+1/2; jj: -y+2, x-y, z; kk: -x+y+2, -x+2, z; ll: -y+2, -x+2, -z+1/2; mm: -x+y+2, y, -z+1/2; nn: x, x-y, -z+1/2; oo: y+1, -x+y+1, -z+1.

IR Spectra. An IR spectrum was obtained for each compound using a SensIR

Technology IlluminatIR FT-IR microspectrometer equipped with a diamond ATR objective. Each spectrum was taken from 650 to 4000 cm-1 with a beam aperture of

100 μm for crystals that were stored in a desiccator for 24 h prior to analysis.

Figure 5.1 IR spectrum for NH4(UO6)2(UO2)9(GeO4)(GeO3(OH)).

Figure 5.2 IR spectrum for K(UO6)2(UO2)9(GeO4)(GeO3(OH)).

Figure 5.3 IR spectrum for Li3O(UO6)2(UO2)9(GeO4)(GeO3(OH)).

Figure 5.4 IR spectrum for Ba(UO6)2(UO2)9(GeO4)2.

UV-vis-NIR. Absorption data were acquired for each compound using a Craic

Technologies UV-vis-NIR microspectrophotometer. Each spectrum was taken from

250 to 1500 nm.

1.8

1.6

1.4

1.2

e 1 [1]_1

a b

r [1]_2

s b

A [1]_3 0.8 [1]_4

[1]_5 0.6

0.4

0.2

0 0 200 400 600 800 1000 1200 1400 1600 Wavelength (nm)

Figure 5.5 UV-vis-NIR spectra for five NH4(UO6)2(UO2)9(GeO4)(GeO3(OH)) crystals.

1.6

1.4

1.2

e [2]_1

a b

r 0.8 [2]_2

s b

A [2]_3

[2]_4

0.6 [2]_5

0.4

0.2

0 0 200 400 600 800 1000 1200 1400 1600 Wavelength (nm)

Figure 5.6 UV-vis-NIR spectra for five K(UO6)2(UO2)9(GeO4)(GeO3(OH)) crystals.

1.4

1.2

0.8

[3]_1

e c

n [3]_2

a b

r 0.6 o

s [3]_3

b A [3]_4

[3]_5 0.4

0.2

0 0 200 400 600 800 1000 1200 1400 1600

-0.2 Wavelength (nm)

Figure 5.7 UV-vis-NIR spectra for five Li3O(UO6)2(UO2)9(GeO4)(GeO3(OH)) crystals.

1.6

1.4

1.2

e [4]_1

a b

r 0.8 [4]_2

s b

A [4]_3

[4]_4

0.6 [4]_5

0.4

0.2

0 0 200 400 600 800 1000 1200 1400 1600 Wavelength (nm)

Figure 5.8 UV-vis-NIR spectra for five Ba(UO6)2(UO2)9(GeO4)2 crystals.

Electron Microprobe Analysis. Elemental analyses were done for single crystals of each compound using a Cameca SX50 electron microprobe. Standards were natural paracelsian (Ba), Ge metal, UO2 (Oak Ridge), and microcline (K).

Quantitative wavelength dispersive analyses were done for U, Ge, K, and Ba.

Qualitative wavelength dispersive scans confirmed the presence of N in 1, and did not reveal the presence of F in any case (which could have been derived from the

Teflon-lined vessels). Oxide abundances are averages of three to five spots analyzed, with the expected value from the structure determination in parentheses (wt %):

1: UO3 = 93.6 (93.0), GeO2 = 5.65 (6.19);

2: UO3 = 93.1 (92.2), K2O = 1.36 (1.38), GeO2 = 5.57 (6.13);

3: UO3 = 93.3 (93.1), GeO2 = 5.70 (6.19);

4: UO3 = 89.9 (89.4), BaO = 4.22 (4.36), GeO2 = 5.58 (5.94).

Thermogravimetric Analysis. Thermogravimetric measurement was done for compound 2 using a Netzsch TG209 F1 Iris thermal analyzer. The sample was loaded into an Al2O3 crucible and heated from 20 to 900 °C at a rate of 5 °C/min under flowing nitrogen gas.

Figure 5.9 TGA for K(UO6)2(UO2)9(GeO4)(GeO3(OH)).

5.2 Results

Crystals of compounds 1 through 4 were readily attained under mild hydrothermal conditions at 220 °C. Structure analysis, spectroscopic studies, and chemical analysis support the assigned compositions of each compound.

Thermogravimetric analysis of 2 indicated only less than 0.3 wt % loss through heating to 900 °C, and powder X-ray diffraction indicated that there was no structural change upon heating to 900 °C.

The structures of compounds 1 through 4 were refined in space group P3¯ 1c.

Each presents essentially identical frameworks of U polyhedra. In each the U(2) and

U(3) cations are present as typical (UO2)2+ uranyl ions with bond lengths ranging from 1.748(10) to 1.843(8) Å over the four compounds. The U(2)-O(5) bonds are the longest, and range from 1.822(7) to 1.843(8) Å, whereas the others are no longer than 1.790(8) Å. Each of the uranyl ions are coordinated by five O atoms that are arranged at the equatorial vertices of pentagonal bipyramids, with the bipyramids capped by the O atoms of the uranyl ions. Bond-valence sums at the U(2) and U(3) sites, calculated using coordination-specific parameters, (Burns et al.,

1997) range from 5.91 to 6.03 vu, consistent with the formal valence of U(VI).

The U(1) cation in each structure is coordinated by six O atoms, all of which also belong to uranyl bipyramids, that are in a distorted octahedral arrangement.

There are two distinct U(1)-O bond lengths in each structure. The U(1)-O(3) bond lengths range from 2.037(6) to 2.060(9) Å over the four structures, whereas the range for the U(1)-O(4) bonds is from 2.095(6) to 2.118(6) Å. Although unusual,

U(VI) cations in distorted octahedral coordination similar to those found here have 83

been reported in several structures (Burns, 2005; Burns et al., 1997). Bond-valence sums at the U(1) site, calculated using coordination-specific parameters, (Burns et al., 1997) range from 5.89 to 6.10 vu in compounds 1 to 4, consistent with the expected formal valence.

The U(1), U(2), and U(3) polyhedra share edges and vertices, resulting in a complex and rather dense framework (Figure 5.4). Consider first the U(2) pentagonal bipyramids that occur in layers perpendicular to [001] at c = 0 and 1/2.

One of these layers is shown in Figure 5.4b. Each U(2) pentagonal bipyramid shares an equatorial edge defined by O(4) atoms with an adjacent U(2) bipyramid, resulting in dimers that are canted about the -3 symmetry axis. These dimers are linked through cation-cation interactions, such that each U(2) uranyl ion donates one cation-cation interaction that is accepted by a U(2) uranyl ion of an adjacent dimer. Each dimer therefore is linked to two others by cation-cation interactions, which results in the layer of U(2) bipyramids that is perpendicular to [001].

The U(1) distorted octahedron is within the layer of U(2) bipyramids, where it is located on the -3 axis. Three of the octahedral edges are also equatorial edges of adjacent U(2) bipyramids.

The U(3) cations are located between the U(1)-U(2) layers (Figure 5.4a), where the pentagonal bipyramids are arranged about the -3 axis such that they occur in trimers with the bipyramids sharing the O(8) vertex. Each U(3) bipyramid shares two of its equatorial edges with U(2) bipyramids, one of which is from each adjacent U(1)-U(2) layer.

The U-centered polyhedra are linked to create a complex framework that contains cavities. Low-valence cations occur in one of these cavities. In the NH4 (1),

K (2) and Ba (4) compounds, the coordination environment about the low-valence cation is octahedral, with the vertices corresponding to symmetrically equivalent O atoms that are part of the uranyl ion associated with the U(2) cation. The interatomic distances are 2.809(7) and 2.773(8) Å for the K and Ba cations, respectively. Li is incompatible with this site owing to its small size. Instead, in the

Li compound, a Li3O group resides in a cavity, with each Li coordinated by five O atoms in a distorted trigonal bipyramidal arrangement with bond distances ranging from 1.75(5) to 2.306(7) Å. In all cases (especially the Li compound (3)), large and elongated displacement parameters indicate positional disorder of the low-valence cation and to a smaller extent the associated O atoms.

The Ge atoms occur in cavities within the framework of U polyhedra that are elongated in the [001] direction (Figure 5.4b). The details of the coordination environments about the Ge sites are quite complex. In the NH4 (1), K (2), and Li (3) compounds the electron density associated with the Ge sites is strongly elongated in the [001] direction. The site was subsequently split and refined as the Ge(1) and

Ge(2) sites that refined to a separation of ∼0.7 Å, each set at half occupancy. The coordination environment about these cations may be loosely defined as trigonal bipyramidal. The equatorial O atoms are the symmetrically equivalent O(1) atoms.

The apexes of the bipyramid are defined by the O(6) and O(8) atoms, each of which exhibit displacement parameters that are elongated in the [001] direction, which is also parallel to the corresponding Ge-O bonds. The O(8) anion is bonded to three 86

U(3) cations, whereas O(6) is shared between two Ge atoms only. If the true coordination environment about the Ge cations is trigonal bipyramidal, there is an infinite chain of these sites extending along [001] and the O(6) site is occupied by

OH. A similar chain was recently reported in the structure of

Ag2[(UO2)3(GeO4)2](H2O)2 (Ling et al., 2010).

However, the elongated displacement parameters of the Ge, O(6), and O(7) sites indicate in general an incompatibility with the extended framework of U- centered polyhedra. It appears that the Ge coordination polyhedra may best be regarded as transitional between tetrahedral and trigonal bipyramidal, and that local configurations differ considerably within the structure.

In the case of the Ba structure (4), splitting the Ge site over two positions did not significantly improve the refinement. Instead, the single Ge site is coordinated by four O atoms with bond distances in the range of 1.741(3) to 1.752(7) Å. The

O(6) site bridges between Ge tetrahedra with a Ge-O-Ge bond angle of 180°. None of the O sites are protonated, consistent with incorporation of Ba in place of a monovalent cation in the corresponding structures of the NH4 (1) and K (2) compounds.

5.3 Discussion

The four uranyl germanates reported herein have complex framework structures that present several unusual characteristics. Foremost among these are the cation-cation interactions involving the U(2) uranyl ion, as this type of linkage occurs in only ∼2% of U(VI) structures. The bonds within the U6+ uranyl ion are very 87

strong, and correspond to about 1.7 valence units in the bond-valence formalism

(Burns et al., 1997). The linkages between the U6+ cation and equatorial ligands of its bipyramids are much weaker, about 0.5 valence units (Burns et al., 1997). In U6+ compounds, cation-cation interactions are uncommon because mild over-bonding occurs at the uranyl-ion O atom that also coordinates another uranyl ion. Where the actinyl ion contains a pentavalent cation (U5+ or Np5+), the bonds are somewhat weaker. In these cases over-bonding at the shared O atom is not significant, as demonstrated by the abundance of cation-cation interactions in compounds containing Np5+ (Forbes et al., 2008).

Cation-cation interactions in actinyl compounds have profound impacts on structure connectivity. Where uranyl bipyramids containing U6+ cations link to other uranyl bipyramids or various oxyanions in the absence of cation-cation interactions, connections are limited to the equatorial ligands of the bipyramids. The result is dominance of sheet structures, and to a lesser extent structures that contain infinite chains (Burns, 2005). Where cation-cation interactions occur, uranyl bipyramids form linkages through both the apical and the equatorial vertices, which favors formation of three-dimensional topologies such as observed in the current study.

The distorted octahedral coordination polyhedron about the U(1) cation is also uncommon, as no uranyl ion is present. These polyhedral geometries and their connectivity result in an unusually dense framework structure. For example, the density of the K compound (2) is 7.29 g/cm3. Compare this to the density of soddyite, (UO2)2(SiO4)(H2O)2, a framework uranyl silicate hydrate, which is 5.09 g/cm3 (Demartin et al., 1992). The framework structure of K5(UO2)2[Si4O12(OH)], 88

which lacks cation-cation interactions, has a density of only 3.92 g/cm3 (Chen et al.,

2005b). Another compound that also lacks cation-cation interactions,

KNa3(UO2)2(Si4O10)2(H2O)4, has a density of 3.34 g/cm3 (Burns et al., 2000). In contrast, the compounds Sr5(UO2)20(UO6)2O16(OH)6(H2O)6 and Cs(UO2)9U3O16(OH)5, both of which contain cation-cation interactions, have densities of 6.54 and 7.33 g/cm3, respectively (Kubatko and Burns, 2006). In a framework structure, cation- cation interactions between uranyl ions permit an overall closer packing of uranium in the structure, and thus a higher density is attainable.

The Ge cations, as well as the low-valence cations, are located in cavities within the framework of uranyl polyhedra. In all cases elongated anisotropic displacement parameters, and in three structures split Ge sites as well, indicate positional disorder and are consistent with the relatively poor fit of these cations within the available sites. Additional diffraction data collected for each compound at

110 K reduced the overall size of the displacement parameters, but did not impact their relative anisotropy. We also examined several plausible twin models to explain the elongated displacement parameters. The twin models did not produce superior refinements, leading us to conclude that local disorder is the cause of the elongated displacement parameters.

Of the more than 360 reported U(VI) minerals and inorganic compounds

(Burns, 2005), there are only 8 U(VI) germanate compounds and 18 similarly complex U(VI) silicate compounds. The previously reported U(VI) germanate compounds have shown a propensity for open ring- or channel-bearing framework structures (Ling et al., 2010), whereas the four new framework germanate 89

compounds presented here demonstrate a highly complex framework dominated by

U polyhedra. The divergence of these structures further emphasizes the importance of cation-cation interactions in structure topologies.

Unlike U(VI) compounds, Np(V) compounds commonly have cation-cation interactions. This has led to the development of a system to categorize Np(V) cation- cation interactions that are a through h based on the local configuration of the ions

(Krot and Grigoriev, 2004). The uranyl germanate frameworks contain a c-type interaction where each uranyl ion participates in two cation-cation interactions.

Each uranyl ion donates a cation-cation interaction that is accepted by a symmetrically identical uranyl ion. In other words, each uranyl ion donates one cation-cation interaction and accepts another from a symmetrically identical uranyl ion. This type of configuration exists in ∼20% of both Np(V) and U(VI) cation-cation interaction compounds. The most common configuration for Np(V) compounds was designated h, and is where the neptunyl ion participates in four cation-cation interactions. Specifically, the Np(V) neptunyl ion donates two cation-cation interactions (one through each O atom), and accepts two cation-cation interactions donated by other neptunyl ions. The most common configuration for U(VI) cation- cation interactions is type a, in which the uranyl ion donates a single cation-cation interaction.

CHAPTER 6:

CONTROLLED NUCLEATION AND GROWTH OF CALCITE IN AN AQUEOUS

SYSTEM

Calcite, a common rock-forming mineral, is among the most prevalent of carbonate mineral phases and may be formed as a marine evaporite, by hydrothermal activity, and a variety of low-temperature processes including biomineralization and diagenesis. Synthetic calcite crystals have been extensively studied as models for calcite-contaminant interactions in environmental systems

(Reeder et al., 2000, 2004; Warren et al., 2001; Phillips et al., 2005; Heberling et al.,

2008; Cai et al., 2010).

The synthesis of calcite reported herein is a precursor to the actinide- incorporation study reported in Chapter 7, in which the incorporation of transuranium elements into the calcite structure was studied to better understand inorganic controls that impact their mobility in the subsurface. The approach was to synthesize crystals with diameters of ~ 500 µm in the presence of transuranium cations, but the radiologic hazard and expense of working with these elements strongly favors relatively simple one-step synthesis approaches that minimize worker exposure to radioactivity and the creation of contaminated materials.

Although there are reported methods for the synthesis of calcite that provide high-

quality crystals of the appropriate size for our work, these approaches are more complex and cumbersome than ideal for working with transuranium elements.

The following is not intended to provide a comprehensive review of calcite formation and dissolution (Morse et al. 2007), rather it is meant to highlight selected methods for growth of synthetic calcite to demonstrate the breadth of synthesis research in this area. This is followed by a simple one-step synthesis method for calcite crystals, with the expectation that others will find this approach useful.

6.1 Synthesis Review

6.1.1 Aqueous-Inorganic

Methods commonly involve mixing a Ca-bearing aqueous solution (i.e. CaCl2,

Ca(OH)2, CaI2, CaF2) with a CO3-bearing aqueous solution (i.e. Ca(HCO3)2, K2CO3,

Na2CO3, MgCO3). Solutions may be stirred (Gómez-Morales et al., 1996; Gao et al.,

2007) or heated (Hu and Deng, 2003). These methods give amorphous (Kitano et al.,

1979) or microcrystalline calcite (Gómez-Morales et al., 1996), crystals as large as

10 m in diameter (Hu and Deng, 2003), and aragonite (Hu and Deng, 2004).

6.1.2 Organic-Mediated Aqueous-Inorganic

Organic molecules (i.e. benzene, EtOH, urea, CTAB, N-butylamine) are commonly used in abiotic syntheses to slow nucleation by separating Ca2+, and CO32- ions (Wakita and Kinoshita, 1985; Hirai et al., 1997; Teng et al., 1998; Sethmann et 92

al., 2005; Chen and Nan, 2011). These approaches include mixing (Wakita and

Kinoshita, 1985; Dalas et al., 1999), heating (Wakita and Kinoshita, 1985; Wang et al., 1999; Nan et al., 2008; Liu et al., 2011), convection (Wang et al., 1999; Nan et al.,

2008; Liu et al., 2011), gas diffusion (Zhu et al., 2011), and biomineralization-like processes (Teng et al., 1998; Xu et al., 1998; Braissant et al., 2003; Faatz et al., 2004;

Sethmann et al., 2005; Xu et al., 2006; Zhu et al., 2011). The results are crystalline or amorphous calcite thin films (Xu et al., 1998), crystals ranging from nanometer to sub-millimeter in diameter (Wakita and Kinoshita, 1985; Hirai et al., 1997; Teng et al., 1998; Sethmann et al., 2005; Xu et al., 2006; Lam et al., 2007; Nan et al., 2008; Liu et al., 2011; Zhu et al., 2011), and mixtures of vaterite and aragonite (Wakita and

Kinoshita, 1985; Wang et al., 1999; Dalas et al., 1999; Braissant et al., 2003, Xu et al.,

2006; Lam et al., 2007; Nan et al., 2008; Chen and Nan, 2011; Zhu et al., 2011).

6.1.3 Template/Seed Aqueous-Inorganic

Templates and seed crystals are used to initiate calcite nucleation in aqueous solution. The frequently used and modified “free-drift” method (Gruzensky, 1967;

House, 1986; Reeder et al., 1990; Zhang and Dawe, 2000) uses seed crystals to encourage crystal growth. In additional studies, nanometer to sub-millimeter diameter crystals of calcite, vaterite, and aragonite grow in aqueous solution on

CaCO3 seed crystals (Sabbides and Koutsoukos, 1993; Lahiri et al., 1997; D’Souza et al., 1999; Naka and Chujo, 2001; Donners et al., 2002; Olszta et al., 2004; Ajikumar et al., 2004; Nehrke et al., 2007; Stack and Grantham, 2010; Wolthers et al., 2011).

Templates (i.e. porphyrin amphiphiles, synthetic and bio-polymers, 93

dendrimers/surfactants) facilitate CaCO3 growth with varying success (Lahiri et al.,

1997; D’Souza et al., 1999; Naka and Chujo, 2001; Donners et al., 2002; Park and

Meldrum, 2002; Aizenberg et al., 2003; Ajikumar et al., 2004).

6.1.4 Mechanical Modification

Methods of varying complexity (i.e. gas diffusion, high-gravity reactive precipitation, rotating packed bed, gas-liquid reaction) have resulted in nanometer to micrometer diameter calcite crystals (Agnihotri et al., 1999; Chen et al., 2000; Sun et al., 2011; Isopescu et al., 2011).

6.2 Experimental Section

The approach for growing calcite crystals is a modification of a simple aqueous diffusion synthesis method for the preparation of sparingly soluble salts

(Fernelius and Detling, 1934), although the original report indicated lack of success in the case of calcite.

Initial saturated solutions of CaCl2 and (NH4)2CO3 are prepared, in this case by the addition of 0.23 grams CaCl2 (99.99%; Sigma) to 1.5 mL ultrapure H2O and

0.36 grams (NH4)2CO3 (99.999%; Alfa Aesar) to 1.5 mL ultrapure H2O. The apparatus consists of a 80-mL Pyrex beaker containing two 2-mL glass vials with

15-mm diameters (Fig. 6.1). The two vials are not in contact with each other or the beaker wall. The saturated solutions are transferred into the 2-mL vials, such that

1.5 mL of CaCl2 solution is in one vial, and 1.5 mL of (NH4)2CO3 solution is in the other. Using a pipette, both 2-mL vials are filled to capacity using water with a pH of 94

2.2 achieved by addition of HCl. Sixty mL of the same HCl-acidified water used to fill the 2-mL vials is then added slowly to the outer beaker, being careful not to disturb the two 2-mL vials. Additional trials were conducted using sixty mL of acidified water produced by adding 1.0 M HCl to give a pH of 1 to 6 in increments of 1, as well as unacidified ultrapure water with an optimum synthesis occurring under experimental conditions with a pH of ~ 2.

Figure 6.1 Photograph (top left) and schematic (top right) of the apparatus for synthesis of calcite crystals from aqueous solution. Beaker shown is 80 mL.

In the course of the studies of actinide incorporation into calcite, this optimized synthesis procedure for calcite has been successfully repeated fifteen times. During these trials, the solution pH in three identical optimized experiments using an Orion PerpHect semi-micro pH electrode. The pH was measured every thirty minutes in the center of the beaker, near the top of the solution as shown in

Figure 1. The pH probe was initially calibrated against standard solutions of pH 4, 7 and 10. Every thirty minutes, the pH of each standard solution and then the pH of the solutions in beakers 1, 2 and 3 were measured, in that order. The pH probe was recalibrated every 300 minutes. Results are shown in Figure 6.4, in which the six measurements (3 standard and 3 beakers) are given for the duration of the experiments. The error bars applied to the beaker measurements are one standard deviation of the measurements for the pH = 7 standard, which averaged 7.03.

A fourth synthesis experiment was conducted that was prepared analogous to the three used for pH measurements, except that purple dye was added to the initial saturated solutions of CaCl2 and (NH4)2CO3. Two video cameras were used to record the progression in this system. This revealed immediate mixing of the saturated solutions with the pH = 2.2 adjusted water that was added to fill the 2-mL vials. Upon filling of the beaker with pH = 2.2 adjusted water, the videos revealed wispy mixing of dye from the 2-mL vial containing (NH4)2CO3 that began immediately but proceeded slowly. A layer depleted in dye developed in the top ten percent of the 2-mL vial containing CaCl2. Over the course of hours the solution in the outer beaker became colored, initially only in the bottom region. The interface between colored and colorless solution migrated slowly upwards and passed the 97

top of the 2-mL vials after about 180 m. Crystals first appeared on the lip of the 2- mL vial containing (NH4)2CO3 at about 340 m. They continued to grow on this vial, and first appeared on the lip of the 2-mL vial containing CaCl2 and on the bottom of the larger beaker at 560 m (Fig. 6.2). At 4050 m the solution in the outer beaker had evaporated to the point of dropping below the tops of the 2-mL vials. Even at this time the solutions contained within the 2-mL vials remained more strongly colored that the solution in the outer beaker.

Figure 6.2 The photos above were taken from a video of an experimental trial in which purple dye was added to the initial saturated solutions of CaCl2 and (NH4)2CO3. The photo on the left was taken after 540 m and calcite crystals have appeared on the lip of the 2-mL vial that was initially loaded with (NH4)2CO3. The photo on the right, taken after 1260 m, shows abundant calcite crystals on both vials. The strong coloration of the solutions in the 2-mL vials demonstrates that complete solution mixing has not occurred in the system.

The products of the synthesis studies were readily identified optically, and were confirmed by single-crystal and powder X-ray diffractometry (Fig. 6.5).

Crystals were imaged with a Leo scanning electron microscope.

6.3 Results and Discussion

Crystals of calcite formed on the edges of the 2-mL vials, within the vials, and on the floor of the beaker. The diameter of these crystals ranged from 10s to 100s of micrometers. When the experiment is carried out using unacidified ultrapure water, the solution becomes cloudy immediately, indicating sufficient nutrients have already moved out of the small vials for precipitation to occur. When the pH is lowered to ~2 by the addition of 1.0 M HCl, the beaker solution remains clear throughout nucleation, and crystals appear after a few hours.

Scanning electron microprobe images collected at 200x reveal significant differences in the reaction products from experiments conducted at initial pH values of 1 through 6, increasing by increments of 1 (Fig. 6.3). Where the pH of the beaker solution is 1 initially, no crystals grow. Although crystals grow when the initial solution pH is in the range of 2 to 6, smaller crystals (and more nuclei) appear in those with pH ranging from 3 to 6. An initial pH of 2 provides superior crystal size and clarity. This result may be attributed to the nucleation buffer created by the

HCl-acidified water.

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The synthesis apparatus creates a system of diffusion of nutrients into an aqueous system that is initially acidic. By starting the process with a relatively high

H+ concentration (pH ~ 2), the interaction of Ca2+ and CO32- is sufficiently inhibited to prevent immediate crystal nucleation. Where the starting pH ranges from 3 to 6, formation of polycrystalline material indicates more rapid nucleation.

The pH of the beaker solution increases due to the entry of (NH4)CO3 from the 2-mL vial (Fig. 6.4). In each of the trials conducted, the initial pH of 2 increases gradually to 2.5 or 3 over 500 to 700 minutes, and then increases to 7 to 7.5 rather rapidly. The exact timing of the onset of the increase in solution pH differs in the three trials. This aspect of the experiment is not expected to be completely reproducible as insertion and removal of the pH probe causes disturbances in a solution that is partially layered. The observation that the pH in each case increases rapidly over tens of minutes, rather than abruptly, suggests that the system is initially buffered by the HCl in the larger beaker. Once it is neutralized, diffusion from the (NH4)CO3 solution causes the pH increase.

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Inclusion of blue dye in one of our trials demonstrated that the solution in the larger beaker does become layered, and that the darker colored solution expands from the bottom of the beaker upwards, until eventually the water in the entire outer beaker is a similar color. However, even at this stage the solution in the two 2-mL vials is more strongly colored, indicating much of the dye remains within them.

Crystals are readily collected for study from this simple apparatus, which also facilitates addition of radionuclide species of interest to the aqueous solutions.

Powder X-ray diffraction does show the presence of vaterite, a calcium carbonate polymorph. These crystals are minimally present relative to calcite, however, and are readily identified by their spherical shape.

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CHAPTER 7:

INORGANIC CONTROLS ON NEPTUNIUM MOBILITY IN THE SUBSURFACE VIA

CRYSTAL GROWTH

The storage of legacy wastes originating from the development of nuclear weapons during the Cold War and the subsequent migration of radionuclides from this waste into the environment concerns the U.S. Department of Energy (Office of

Science, Department of Energy, 2007a). Field-scale studies of actinide mobility in the environment have been conducted at DOE sites (Kersting et al., 1999; Hixon et al., 2010; Kaplan et al., 2011), but data for the creation of predictive models remains insufficient (Office of Basic Energy Sciences, Department of Energy, 2007; Powell et al, 2011; Zavarin et al, 2012).

Neptunium does not occur naturally in any significant amount. It is a byproduct of the uranium-based nuclear fuel cycle and was produced and concentrated during Cold War-era nuclear weapons production (Forbes et al., 2008;

Ewing, 2010). Neptunium-237 has been listed as an environmental contaminant of concern by the DOE (Office of Science, Department of Energy, 2007a). This radionuclide is of environmental importance because it occurs as Np(V) under oxidizing conditions, which is soluble in water. The isotope has a half-life of 2.14

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million years, and it is expected to be among the highest contributors of activity from spent fuel one million years after removal from a reactor (Brookins, 1984).

The coordination chemistry of Np(V) is similar to that of U(VI). Np(V) is coordinated by two apical oxygen atoms to form the nearly linear neptunyl ion,

(NpO2)+. This ion is further coordinated by four, five, or six equatorial ligands, forming square, pentagonal, or hexagonal bipyramidal polyhedra. While it is tempting to make predictions about the environmental behavior of Np(V) based on that of the more studied U(VI) because they share similar coordination polyhedra, significant topological divergence has been observed (Forbes et al., 2008). Notably, the neptunyl ion is far more likely to participate in cation-cation interactions (CCIs).

These occur when an oxygen atom of the neptunyl ion serves also as an equatorial oxygen atom in a neighboring Np(V) polyhedron. Because the bonding requirements of the uranyl oxygen atoms are nearly met, they are far less likely to participate in

CCIs.

CCIs are not expected to play a direct role in this study. However, it is expected that Np(V) will behave differently than U(VI) under similar experimental conditions. Previous studies have suggested that (UO2)2+ may replace Ca2+ in the structure of synthetic calcite and be coordinated in the equatorial plane by 5 or 6 oxygen atoms belonging to some number of mono- and/or bi-dentate carbonate triangles (Figure 7.1) (Reeder et al., 2000).

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In a departure from what has been observed with U(VI), studies of Np(V) coordination within the calcite structure have suggested that (NpO2)+ will replace

Ca2+ and be coordinated in the equatorial plane by four mono-dentate carbonate triangles (Heberling et al, 2008a); meanwhile, the crystal structures of the only two published inorganic Np(V) carbonates contain (NpO2)+ coordinated by six monodentate carbonate triangles (Forbes et al., 2008).

Unlike uranium present in the subsurface of DOE sites, neptunium lacks the abundance necessary to form hydrated minerals. In laboratory studies, however,

Np(V) has shown a propensity for incorporation into U(VI) minerals (Burns and

Klingensmith, 2006). With regard to rock-forming mineral species, the behavior of the actinyl ion has been explored to some extent previously. Studies of the uranyl ion have been undertaken with regard to synthetic calcite and aragonite (Reeder et al., 2000; Reeder et al., 2004) as well as natural calcite (Kelly et al., 2006). The

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neptunyl ion has been investigated within the calcite structure (Heberling et al.,

2008a; Heberling et al., 2008b) and a surface complexation model has been developed for the sorption of lanthanides Eu(III) and Sm(III) and actinides Np(V),

Pu(V), and Pu(IV) to calcite (Zavarin et al., 2005).

In the aforementioned studies of calcite, the conclusions are not unambiguous. For uranium, investigations of the syntheses and structural environments of uranyl-incorporated calcite and aragonite have suggested that aragonite may incorporate U(VI) better than calcite due to fewer coordination constraints and that growth method may affect incorporation (Reeder et al., 2000;

Reeder et al., 2004). A study of the structural position and stability of the uranyl ion in natural calcite suggested that the uranyl environment becomes more stable over geologic time (Kelly et al., 2006).

Studies of uranyl incorporation in calcite have been underway for more than ten years, but exploration of the interaction between the neptunyl ion and calcite are just beginning. In a previous study, neptunyl-incorporated rinds were grown on seed crystals of calcite, indicating that calcite has a higher affinity for the neptunyl ion than the uranyl ion (Heberling et al., 2008a). The authors found Np(V) incorporation of calcite in a range of 1900 to 5100 ppm. The concentration of U(VI) was two orders of magnitude lower. In another study, neptunyl-doped calcite particles were synthesized, and the authors suggested that neptunyl adsorbed to the surface might become incorporated through surface dissolution and re-precipitation

(Heberling et al., 2008b). A surface complexation model for the sorption of specific lanthanides and actinides to calcite indicates that Np(V) sorption is weaker than 108

that of Sm(III) and Eu(III), Pu(V) sorption to calcite is similar to that of Np(V), and

Pu(IV) sorption to calcite is much greater than that of Pu(V) (Zavarin et al., 2005).

Studies of actinide interactions with gypsum are almost nonexistent. Some exploration into lanthanide and transition metal behavior in gypsum syntheses has been undertaken (de Vreugd et al., 1994), but only one actinide study has been published (Schmidt et al., 2009). This study compared incorporation versus adsorption behavior of Eu(III) and Cm(III) to aragonite and gypsum, and suggested a tendency for structural incorporation within aragonite and surface adsorption to gypsum for both ions.

Calcite was chosen for this study because it is a common rock-forming mineral found extensively in soils and groundwater aquifers (Kelly et al., 2003).

Gypsum, the most common of the sulfate minerals, is an abundant mineral in Earth’s crust that occurs commonly with sedimentary rocks like limestone. Both calcite and gypsum present a structure with a large cation that has potential for substitution by the neptunyl ion, while their structural differences allow for initial steric-based discussion of incorporation mechanisms.

Using the method described in Chapter 6 for the growth of calcite, I have synthesized both calcite and gypsum in the presence of Np(V). In a parallel study, calcite and gypsum were synthesized in the presence of U(VI). The complete experimental method, results and discussion follow.

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7.1 Methods

Caution: 237Np is a strong alpha emitter and represents a serious health risk. The methods discussed herein must be performed using appropriate facilities and personnel trained for handling radioactive materials.

Synthesis. Calcite was synthesized by the method described in Chapter 6 in which a saturated solution of CaCl2 was brought into close contact with a saturated solution of (NH4)2CO3, separated only by an aqueous barrier. Two 2-mL glass vials were placed carefully inside an 80-mL Pyrex beaker. Each vial was filled to ¾ with the prepared saturated solutions; one with CaCl2 and the other with (NH4)2CO3. The aqueous barrier was prepared from 60 mL deionized water and an aqueous NpO2+ solution. The remaining ¼ vial space was filled with the Np-containing aqueous barrier solution. Using a 10-mL pipette, the remaining aqueous barrier solution was carefully added to the beaker.

Since Np is expected to substitute for Ca, these trials were conducted by the addition of 400 and 1000 PPM Np(V) for calcite and gypsum relative to the initial quantity of Ca2+ in the reaction system where Ca represents 1 million parts. “Low” concentration refers to 400 PPM; “high” concentration refers to 1000 PPM. The concentration in solution was based on the concentration of the cation present in each synthesis according to the following equation:

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In this equation, Npppm is the desired ppm concentration, xgr is the amount of

Ca2+ in the reaction system (in g), and Npgr is the amount of Np (g) needed.

Gypsum was prepared using the same protocol. Both syntheses were also carried out in the presence of UO22+. The exact synthesis parameters for calcite and gypsum in the presence of Np(V) and U(VI) are shown in Table 7.1.

Preparation and Verification of Np(V). High-purity 237NpO2 was obtained from the Isotopes Division of Oak Ridge National Laboratory. A laboratory stock solution was created previously by dissolving 200 mg NpO2 in concentrated HNO3 in a Teflon-lined Parr reaction vessel at 150°C for 3 days. Once the solution had cooled, a UV spectrum was collected to verify that the oxidation state was +5 and +6. A small amount of NaNO2 was added to the solution to reduce Np(VI) to Np(V). A second UV spectrum was collected to verify that all the Np had been reduced to +5.

To address safety concerns associated with hydrothermal Parr reaction vessel experiments, the Np(V) was re-precipitated using NaOH, centrifuged, washed, dried, and dissolved in 1 M HCl. A 10 mM Np(V) stock solution was prepared for the aforementioned experiments.

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TABLE 7.1

SYNTHESIS PARAMETERS FOR U- AND NP-DOPED CALCITE AND GYPSUM.

CaCl2 (NH4)2CO3 Na2SO4 U solution Np solution U-doped Calcite (400 ppm) 1.5 mL of 1.7 M solution 1.5 mL of 2.5 - 17 µL of 0.01 - M solution M U stock U-doped Calcite (1000 ppm) 1.5 mL of 1.7 M solution 1.5 mL of 2.5 - 42 µL of 0.01 - M solution M U stock Np-doped Calcite (400 ppm) 1.5 mL of 1.7 M solution 1.5 mL of 2.5 - - 17 µL of 0.01 M M solution Np stock Np-doped Calcite (1000 ppm) 1.5 mL of 1.7 M solution 1.5 mL of 2.5 - - 42 µL of 0.01 M

112 M solution Np stock

U-doped Gypsum (400 ppm) 1.5 mL of 1.7 M solution - 1.5 mL of 2.5 6 µL of 0.1 M - M solution U stock U-doped Gypsum (1000 ppm) 1.5 mL of 1.7 M solution - 1.5 mL of 2.5 16 µL of 0.1 - M solution M U stock Np-doped Gypsum (400 ppm) 1.5 mL of 1.7 M solution - 1.5 mL of 2.5 - 59 µL of 0.01 M M solution Np stock Np-doped Gypsum (1000 ppm) 1.5 mL of 1.7 M solution - 1.5 mL of 2.5 - 152 µL of 0.01 M solution M Np stock Note: U and Np solutions were added to 60 mL barrier solution prior to addition of barrier solution to the 80 mL beaker. CaCl2, (NH4)CO3 and Na2SO4 concentrations are approximations based on the solubility of the starting material in water under laboratory conditions.

Solution samples were removed and reserved for elemental characterization from the barrier solution at regular 2-day intervals until the presence of crystals was readily apparent. The pH of the barrier solution was measured and recorded at regular 2-day intervals. The solutions were stored in 2-mL capped centrifuge tubes that were additionally sealed with Parafilm.

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TABLE 7.4

INTERVAL PH MEASUREMENTS FOR U- AND NP-DOPED CALCITE.

pH Water (g) 0.1 M HCl µL Before After Day 1 Day 3 Day 5 Day 7 Np-doped Calcite (400 ppm; 1) 60.2194 550 3.4 2.18 - 7.02 7.01 7.35

114 Np-doped Calcite (400 ppm; 2) 60.0415 550 3.24 2.17 2.36 6.93 6.95 7.05 Np-doped Calcite (1000 ppm; 1) 60.0211 450 2.83 2.19 2.42 7.01 6.85 7.40 Np-doped Calcite (1000 ppm; 2) 60.0428 450 2.85 2.20 2.49 7.23 6.92 7.25 U-doped Calcite (400 ppm; 1) 60.1218 150 4.66 2.15 2.58 6.62 6.87 7.37 U-doped Calcite (400 ppm; 2) 60.1093 150 4.12 2.17 2.94 6.67 7.10 7.00 U-doped Calcite (1000 ppm; 1) 60.0123 100 3.80 2.19 2.93 6.72 7.12 7.13 U-doped Calcite (1000 ppm; 2) 60.0842 100 3.86 2.15 2.54 6.75 6.79 7.39 Blank 59.9501 450 4.71 2.21 2.11 7.08 7.30 7.35 Note: The pH of the barrier solution was adjusted by the addition of 0.1 M HCl following addition of U or Np solution to a starting pH of ~2.

TABLE 7.5

INTERVAL PH MEASUREMENTS FOR U- AND NP-DOPED GYPSUM.

pH 115 Water (g) Day 0 Day 1 Day 3 Day 5 Day 7 Day 9 Day 11

Np-doped Gypsum (400 ppm; 1) 60.0684 5.63 4.67 5.35 5.00 5.53 5.31 5.48 Np-doped Gypsum (400 ppm; 2) 60.1150 5.30 5.65 5.15 5.01 5.16 5.59 5.24 Np-doped Gypsum (1000 ppm; 1) 60.2548 5.77 4.73 4.90 4.90 5.02 4.86 4.91 Np-doped Gypsum (1000 ppm; 2) 60.7998 4.99 4.71 4.99 4.86 5.12 4.82 5.16 U-doped Gypsum (400 ppm; 1) 60.1072 4.02 4.07 4.30 4.22 4.26 4.22 4.11 U-doped Gypsum (400 ppm; 2) 60.0318 4.01 4.04 4.29 4.25 4.26 4.19 4.06 U-doped Gypsum (1000 ppm; 1) 60.0973 3.53 3.61 3.86 3.84 3.78 3.74 3.49 U-doped Gypsum (1000 ppm; 2) 60.3855 3.54 3.60 3.86 3.83 3.73 3.73 3.51 Blank 60.3335 5.50 5.75 5.55 5.55 5.47 5.56 5.33 Note: The pH of the barrier solution was not adjusted following addition of U or Np solutions.

Characterization. Inductively coupled plasma mass spectrometry (ICP-MS) may be employed in solution or solid mode to determine elemental or isotopic concentrations (Vance et al., 1998; Reeder et al., 2000). Concentrations of uranium and neptunium were measured in medium resolution for solution samples using a high-resolution magnetic sector ELEMENT 2 ICP-MS. Medium resolution was chosen to avoid spectral interferences. Solution samples were diluted to ppb range of Np or

U in 5% HNO3 and prepared in duplicate or triplicate when possible. A 100 ppb

Tl/Bi internal standard spike was used to monitor for instrument drift. Neptunium and uranium solutions of verified concentration were used to prepare external standard ppb-range solutions. Solid samples were ablated by a 213 nm ND-YAG

New Wave Research Laser Ablation system. Because no solid standard was available for these samples, the ratio of Ca-43 to actinide signal (in counts per second) was observed resulting in an upper limit calculation for actinide ppm in the solid relative to Ca.

Uncertainties were calculated based on the standard deviation of the measured intensity for U-238, Np-237, Bi-209 and Tl-205, where applicable. The uncertainties on Np and U concentration values are propagated combined percentages based on normalization to an internal standard, Bi-209 or Tl-205. The average uncertainty for each set of data is as follows: calcite solution, U (3%), Np

(7%); calcite solid, U (8%), Np (6%); gypsum solution, U (3%), Np (3%); gypsum solid, U (3%), Np (2%).

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7.2 Results

Synthesis. Calcite crystals were readily visible on the edges of the glass vials after three days in both high and low concentration experiments. Crystals continued to nucleate and grow along the base of the vials and the 80-mL glass beaker. Once the pH of the barrier solution reached a constant, repeatable value, the crystals were removed from solution, washed with ultrapure water and dried. Crystals ranged from 100- to 500 micrometer and exhibited a characteristic rhombohedral habit.

Vaterite crystals were identified visually based on habit and known presence during the synthesis optimization of pure calcite reported in Chapter 6.

Gypsum crystals were readily visible on the edges of the glass vials after three days. Crystals continued to grow along the base of the vials and the 80-mL glass beaker in radiating clusters. Once the pH of the barrier solution reached a constant value, the crystals were removed from solution, washed with ultrapure water and dried. Individual gypsum blades were as long as 5 millimeters.

Characterization. ICP-MS solution. Samples of both high and low concentration barrier solutions from neptunium-spiked calcite experiments show a significant drop in neptunium concentration at Day 3.This corresponds with the time at which crystals are first observed. In uranium experiments, the uranium concentration decreases slightly and then increases slightly, likely a result of evaporation. Relative to the results seen in the neptunium experiments, the uranium concentration remains constant in solution.

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Solution results for gypsum are noticeably unlike those for calcite. The concentration of neptunium in the barrier solution remains constant with a slight increase attributed to evaporation. The same is true for the concentration of uranium in the barrier solution of the parallel uranium experiment.

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119

ICP-MS solid. Laser ablation ICP-MS results for calcite provide at best an upper limit for Np(V) incorporation because no standard with a similar matrix is available for these studies. Figure 7.4 demonstrates the ability to measure Np-237 in a calcite solid by laser ablation.

Figure 7.4 Time-resolved Np-237 laser ablation results in a calcite solid. Np-237 values shown in counts per second.

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To estimate the upper limit, the counts per second measured for Np or U is compared as a ratio to the counts per second measured for Ca-43. The inverse of this value is then multiplied by the calculated ppm of total Ca in the mineral.

Compared with solid mode ICP-MS results for uranium in calcite, the upper limit for

Np(V) appears to be as much as an order of magnitude higher than for U(VI). Solid mode ICP-MS results for gypsum were inconclusive due to the fragile nature of the bladed crystals. Gypsum crystals were instead dissolved in five percent HNO3- and prepared for solution analysis by ICP-MS. As seen in Figure 7.4, the concentration of

An present in gypsum is significantly lower than that seen in calcite. The difference between Np and U in dissolved gypsum crystals is more difficult to ascertain. The low levels of An present in the gypsum solid are consistent with the high levels that remain in the reaction solution.

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Figure 7.5 ICP-MS solid results for CALCITE and GYPSUM. Parts per million values represent an upper limit for the concentration of An in the solid material.

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7.3 Discussion

The experimental data confirm our hypothesis that neptunium may be incorporated into calcite under ambient conditions. The absence of neptunium in the barrier solution following crystal growth as shown by ICP-MS in solution mode and the presence of substantial neptunium relative to calcium in the crystals as shown by ICP-MS in solid mode suggest that the neptunyl ion may substitute for calcium in the calcite structure. Charge balance may be accounted for by considering a loss of carbonate triangles occurring as a result of structural disorder. In the event that neptunium adsorbed to the glass beaker, there is an expectation that the neptunium concentration in solution would have decreased at Day 1 rather than

Day 3 coinciding with crystallization. Of additional concern, the precipitation of

Np2O5 is unlikely under these experimental conditions. The formation of Np2O5 is pH and concentration dependent such that it would occur in solutions near pH 8.5 with Np(V) concentration near 10-4 M (Runde, 2000). NpO2+ is the dominant Np species in solution at a pH lower than 7 and is not expected to hydrolyzed appreciably (Morss et al, 2006).

The results from ICP-MS in solution and solid modes for calcite suggest an affinity for neptunium relative to uranium of at least an order of magnitude. This may be attributed to a difference in –yl size and charge.

The experimental data for gypsum, however, do not rigorously support any incorporation mechanism for neptunium or uranium. Because data gathered from

ICP-MS in solid mode was inconclusive, data were collected in solution mode from dissolved crystals. These data strongly suggest less interaction between gypsum and 123

actinide contaminants than is seen with calcite. These results are consistent with the reaction solution data gathered for gypsum in which no significant decrease in Np or

U is seen during crystal growth. The minimal presence of Np and U in the solution data from dissolved gypsum crystals may be attributed to surface sorption, rather than structural incorporation.

Hypothetical models based on the steric constraints of the crystal structures of calcite and gypsum provide some indication of the potential host site for an incorporated actinyl ion and insight into the results gathered from solid and solution analysis. In calcite, shown in Figure 7.5, the neptunyl ion might be expected to fit into the structure in a number of ways including direct substitution of NpO2+ as the –yl ion for Ca2+, Np5+ not in the form of an –yl ion for Ca2+, or a combination of the two. In natural calcite, substitution of Ca2+ by divalent cations is common, but substitution by NpO2+ would require structural flexibility. To achieve charge balance, vacancies must be created in the structure by the exclusion of Ca2+ or CO32-, or potentially by incorporating an additional cation, such as H+.

124

Figure 7.6 In the trigonal structure of calcite, Ca2+ is coordinated by six monodentate CO32- triangles. In nature, Ca2+ is commonly replaced by Mg2+, Sr2+ and Fe2+.

The composition of gypsum, meanwhile, is mostly without variation, although isomorphous substitution for Ca2+ does occur (Shen et al., 2001). The most common variation in gypsum chemistry is dehydration to anhydrite. The presence of structural water and the layered nature of the atomic structure may restrict its ability to incorporate NpO2+ through disorder.

Figure 7.8 In the monoclinic structure of gypsum, each Ca2+ is coordinated by six oxygens of SO42- groups and by two water molecules. In nature, Ca2+ is not commonly substituted in gypsum.

126

Additional studies of carbonates and sulfates grown in the presence of neptunium and uranium are underway and have shown similar results such that the carbonates may be incorporating neptunium significantly more so than uranium, while sulfates tend to exclude both neptunium and uranium.

127

CHAPTER 8:

CONCLUSIONS AND FUTURE WORK

8.1 Importance of this research

The fifteen elements that make up the bottom row of the periodic table both terrify and intrigue. The acquisition of nuclear weapons, non-proliferation and arms reduction treaties, environmental remediation of Department of Energy sites, the accidents at Fukushima Dai-Ichi, a nuclear energy renaissance in the face of a fossil fuel shortage are all realities associated with the actinides – the bottom row of the periodic table – in 2013.

The fundamental study of actinide chemistry contributes to the broader, applied aspects of fields like radiochemistry, geochemistry and nuclear engineering by providing a starting point for structural, thermodynamic and field-scale data collection. Each new U(VI) crystal synthesized adds to a library of uranium materials with increasingly better refined atomic parameters, bond lengths and angles. The benefit of understanding these materials at the atomic scale arises in the ability to model the behavior of U(VI) in a multitude of environmental settings – both natural and engineered. Similarly, the study of Np(V) incorporation into mineral phases at the bench-top level provides valuable information about the way

128

that neptunium might behave in the subsurface – a real concern owing to the legacy contamination of native soils.

This work explores the structural diversity of U(VI) uranyl germanates relative to U(VI) uranyl silicates and investigates the structural constraints on Np(V) mobility in the subsurface through the growth of common, rock-forming minerals.

8.2 Uranyl Germanates

The number of U(VI) uranyl germanates has grown significantly with the addition of this work. In Chapter 4, I described an open-framework U(VI) uranyl germanate, Cs2[(UO2)(Ge2O6)](H2O), that is one of only three topologically identical to a U(VI) uranyl silicate, RbNa[(UO2)(Si2O6)](H2O) (Wang et al., 2002). Although framework structures and the polymerization of germanate tetrahedra are common for germanate compounds, this is the first reported uranyl compound with four- membered rings of germanate tetrahedra. In Chapter 5, I described a set of four isotypic U(VI) uranyl germanate compounds with dense framework structures. The compounds – NH4[(UO6)2(UO2)9(GeO4)(GeO3(OH))] (1),

K[(UO6)2(UO2)9(GeO4)(GeO3(OH))] (2), Li3O[(UO6)2(UO2)9(GeO4)(GeO3(OH))] (3), and Ba[(UO6)2(UO2)9(GeO4)2] – contain chains of GeO5 tetrahedra, distorted U octahedra, and cation-cation interactions, unique structural features that were described in detail in Chapter 5. Most unexpected was the occurrence of cation- cation interactions, but this finding will contribute the study of these rare interactions in U(VI) compounds.

129

The complexity of U(VI) uranyl germanates is apparent in the predominance of framework structures relative to U(VI) uranyl silicates. Although there is no direct application for this work, the fundamental study of U(VI) uranyl germanates contributes to the overall understanding of U(VI) uranyl chemistry by adding to a systematic exploration of the interactions between U(VI) and various chemical systems.

Future work in continuation of the comparison of U(VI) uranyl germanates and silicates should include the synthesis of silicate compounds under similar conditions as germanates, a reversal of the approach taken herein. To further the study of cation-cation interactions, a similar set of U(VI) uranyl germanate experiments should be undertaken in a system where pressure and temperature are modified such that pressure is increased and temperature is lowered to achieve the same results.

8.3 Neptunium Incorporation

Before this study, the methods for monitoring actinide interactions with minerals like calcite were tedious and undesirable for obtaining rigorous, reproducible results. The ability to synthesize large crystals of calcite and gypsum in solution greatly impacted the success of this work. The results provided herein suggest that Np(V) mobility in the subsurface may be slowed by interactions with carbonates, but there is much more still to be understood.

The data gathered and presented here suggest a Np(V) affinity for calcite relative to gypsum. The same is true for Np(V) relative to U(VI) during the synthesis 130

of calcite. These data in their current form, however, are hardly more than qualitative. Although each experiment was carried out in duplicate, additional characterization in triplicate is required to demonstrate the reproducibility of the

ICP-MS solution and solid results. Further, an investigation of Np-237 concentration in calcite samples based upon crystallite size might offer some insight into a growth- based mechanism of incorporation and explain the observed variation in Np-237 concentration in solid calcite samples.

Future work should also include thermodynamic and solubility studies of

Np(V)-doped crystals. Coupled with modeling and high-energy structural studies, this future work would provide conclusive evidence of the local environment and stability of the neptunyl within the calcite structure. Ongoing studies of Np(V) interactions with carbonates, sulfates, phosphates and borates will provide rigorous parameters for a discussion of the crystal chemical constraints on Np(V) incorporation into rock-forming minerals – a valuable contribution toward the creation migration models for actinides in the subsurface.

131

APPENDIX A:

PROFESSIONAL DEVELOPMENT

A.1 Publications

Weng, Z., Wang, S., Ling, J., Morrison, J.M., Burns, P.C. (2012) “A U(VI) Coordination Intermediate Between a Tetraoxido Core and a Uranyl Ion with Cation-Cation Interactions.” Inorganic Chemistry 51, 7185-7191.

Morrison, J.M.; Moore-Shay, L.J.; and Burns, P.C. (2011) “U(VI) Uranyl Cation-Cation Interactions in Framework Germanates.” Inorganic Chemistry, 50, 2272- 2277.

Ling, J.; Morrison, J.M.; Ward, M.; Poinsatte-Jones, K.; and Burns, P. C. (2010) “Syntheses, Structures, and Characterization of Open-Framework Germanates.” Inorganic Chemistry, 49, 7123-7128.

A.2 Media Contributions

Morrison, J. (2013) “How ocean science saves money by hitching a ride.” BoingBoing (web) .

Morrison, J. (2013) “#AAASmtg 2012 Flashback with John Timmer.” Figure One Blog (web) .

Morrison, J. (2013) “Dispatch from ScienceOnline2013.” Figure One Blog (web) .

Morrison, J. (2013) “How to Find a Science Writing Mentor.” Figure One Blog (web) .

Morrison, J. (2013) “Could Scientists Have Prevented the Fukushima Meltdown?” Slate (web) 132

Morrison, J. (2012) “Dental sedation calms patients, courts controversy.” Chicago Tribune (print/web) .

Morrison, J. (2012) “Researchers say order of introducing food to babies plays no role in developing food allergies.” Chicago Tribune (print/web) .

Morrison, J. (2012) “Molecular scientist hopes to synthesize a safer cancer drug.” Chicago Tribune (print/web) .

Morrison, J. and J. Janega (2012) “A Q & A primer behind Friday's story about ant collection.” Chicago Tribune (web) .

Morrison, J. (2012) “School of Ants: Citizens recruited to help take ant census.” Chicago Tribune (print/web) .

Morrison, J. (2012) “Study of athletes parses triumph, pride.” Chicago Tribune (print/web) .

Morrison, J. (2012) “The science of body temperature and outside heat.” Chicago Tribune (print/web) .

Morrison, J. (2012) “Vitamin D gets frequent testing, but the results are a bit quizzical.” Chicago Tribune (print/web) .

Morrison, J. (2012) “CDC proposes testing baby boomers for hepatitis C.” Chicago Tribune (print/web) . 133

Morrison, J. (2012) “Bringing Science to the Public in Three Easy Steps.” Frontiers in Energy Research (web) .

Morrison, J. (2012) “Can Science Save Us? Mourdock Sees a Savior in Science.” Scientific American Guest Blog (web) .

Morrison, J. (2012) “The Student Face of the EFRC: Interview with Undergraduate Researcher Gene Nolis.” Frontiers in Energy Research (web) .

Morrison, J. (2012) “A New Era of Science Funding - Part 2: Kickstarter Success and #IamScience.” Soapbox Science, NatureBlogs (web) .

Morrison, J. (2012) “1 Year Later, What Does Fukushima Mean for Nuclear Research?” Scientific American Guest Blog (web) .

Morrison, J. (2012) “The Disappearing Actinides, and Other Frustrations from the Bottom Row of the Periodic Table of the Elements.” Scientific American Guest Blog (web) .

Morrison, J. (2012) “Polymer Chains Could Help Electrons Go the Distance.” Frontiers in Energy Research (web) .

Morrison, J. (2011) “Science on a Mission: Engineering a Sustainable Future for Haitians without Homes.” Scientific American Guest Blog (web) .

Morrison, J. (2011) “Rad Science: Getting to Known Tomorrow's Nuclear Scientists.” Scientific American Guest Blog (web) .

134

Morrison, J. (2011) “Increasing Predictability in Thorium-based Fuels.” Frontiers in Energy Research (web) .

Morrison, J. (2011) “Conversation Piece: The Evolution of Nuclear Science.” Scientific American Guest Blog (web) .

Morrison, J. (2011) “Keeping Up with the f-Block.” Frontiers in Energy Research (web) .

A.3 Invited Lectures and Engagements

Uranium: History of an Element. Uranium: Cradle to Grave, Mineralogical Association of Canada short course, Winnipeg, Canada; 2013, Invited to write chapter.

The Accidents at Fukushima Dai-Ichi: Exploring the Impacts of Radiation on the Ocean, Tokyo, Japan; 2012, Invited to attend as journalist/researcher.

Siemens Competition Research Workshop for Local Middle and High School Students, University of Notre Dame; 2012, Invited to speak about finding reliable sources, science literacy and science journalism.

The Career Center Diversity Reception, University of Notre Dame; 2012, Invited to speak to students, faculty, and employers.

Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China; 2011, Invited to present research to students and faculty.

A.4 Conference Attendance and Presentations

AAAS Annual Meeting (2013) – Boston, Massachusetts In attendance, press

ScienceOnline (2013) - Raleigh, North Carolina In attendance

The Accidents at Fukushima Dai-Ichi: Exploring the Impacts of Radiation on the Ocean (2012) - Tokyo, Japan 135

In attendance

Geological Society of America (2012) - Charlotte, North Carolina Organizer, "Investigating the Future of Uranium in the Geosciences: An Investigation of Environmental Studies and Applications"

ScienceWriters (2012) - Raleigh, North Carolina In attendance

American Chemical Society (2012) - Philadelphia, Pennsylvania Oral presentation, "Comparative study of the Np(V) incorporation behavior of calcite and gypsum"

Women in Science Symposium: Big Ideas, Big Impact (2012) - Chicago, Illinois In attendance, press

SBR Contractor-Grantee Workshop (2012) - Washington, DC Poster presentation, "Inorganic Controls on Neptunium Mobility in the Subsurface"

Materials Research Society (2012) - San Francisco, California Poster Presentation, "A Comparative Study of the Np(V) Incorporation Behavior of Calcite and Gypsum"

American Chemical Society (2012) - San Diego, California In attendance, press

AAAS Annual Meeting (2012) - Vancouver, Canada In attendance, press ScienceOnline (2012) - Raleigh, North Carolina In attendance

AVS Symposium & Exhibition (2011) - Nashville, Tennessee Oral Presentation, "U(VI) Uranyl Cation-Cation Interactions in Framework Germanates"

Migration (2011) - Beijing, China Oral presentation, "Co-precipitation of Np(V) into rock-forming minerals"

American Chemical Society (2011) - Denver, Colorado In attendance

Energy Frontier Research Centers Summit & Forum (2011) - Washington, DC In attendance, Materials Science of Actinides

136

SBR Contractor-Grantee Workshop (2011) - Washington, DC Poster presentation, "Inorganic Controls on Neptunium Mobility in the Subsurface"

American Chemical Society (2011) - Anaheim, California Oral presentation, "U(VI) uranyl cation-cation interactions in framework germanates"

Pacifichem (2010) - Honolulu, Hawaii Oral presentation, "Co-precipitation of Np(V) into rock forming minerals"

International Mineralogical Association (2010) - Budapest, Hungary Oral presentation, "Synthesis and structural characterization of four new U(VI) germanate compounds"

Materials Science of Actinides EFRC Review (2010) - University of Notre Dame Poster presentation, "Synthesis and structural characterization of four new U(VI) germanate compounds"

American Chemical Society (2010) - San Francisco, California Poster presentation, "Synthesis and structural characterization of four new U(VI) germanate compounds"

A.5 Professional Memberships

Society of Environmental Journalists 2013 - Present

Investigative Reporters and Editors 2013 - Present

American Geophysical Union 2012 - Present

National Association of Science Writers 2011 - Present

American Association for the Advancement of Science 2011 - Present

American Chemical Society 2008 - Present

137

Geological Society of America 2006 - Present

Materials Research Society 2012 - 2013

American Vacuum Society 2011 - 2012

Association for Women in Science 2011 - 2012

A.6 Students Mentored

Rachel Hoffman, Marian High School, Mishawaka, Indiana 2011 - 2012

Maria Reimi, Washington and Lee University 2011 - 2012

Christopher Schreyer, University of Notre Dame 2010 - 2012

Amanda Siemann, University of Notre Dame 2009 - 2011

Dana Lind, Marian High School, Mishawaka, Indiana 2009 - 2011

Laura Moore-Shay, University of Notre Dame 2008 - 2010

Kelsey Poinsatte-Jones, University of Notre Dame 2008

138

A.7 Outreach

Chemistry Demo Team, University of Notre Dame Team Member 10/2011 - 08/2012

Graduate Recruitment and Admissions, University of Notre Dame Recruiter 09/2011 - 08/2012

Frontiers in Energy Research, U.S. Dept. of Energy Editorial Board 02/2011 - 05/2012

Notre Dame Energy Center / Sustainable Energy Initiative Student Advisory Board 01/2011 - 12/2011

University of Notre Dame Graduate Student Union Professional Development Committee 01/2011 - 05/2011

Upward Bound College Preparatory Program Chemistry tutor 09/2010 - 05/2011

Geological Society of America Annual Meeting Recruiter, Civil Engineering and Geological Sciences 2008, 2009, 2010, 2011, 2012 (also in attendance 2006, 2007)

139

APPENDIX B:

SYNTHESIS CONDITIONS FOR EXPERIMENTS

B.1 Uranium Germanates

140

TABLE B 1

LITHIUM URANIUM GERMANATES*

Name GeO2 Base – LiOH H2O U Conc. pH Temperature Notes

U-Acetate 4.24 M 141 UgeLi- 0.2216 1.35 not to be

1 g 0.2215 825 µL 0.0540 g 0.0537 mL 0.0900 12.57 150 redone UgeLi- 0.2216 1.35 2 g 0.2216 825 µL 0.1145 g 0.1153 mL 0.2000 12.36 - UgeLi- 0.2216 1.35 3 g 0.2214 825 µL 0.2862 g 0.2856 mL 0.5000 11.13 - UgeLi- 0.2216 1.35 4 g 0.2218 825 µL 0.5724 g 0.5721 mL 1.0000 6.41 - UgeLi- 0.2216 1.35 5 g 0.2213 825 µL 1.1448 g 1.1446 mL 2.0000 5.56 -

* For each sample, mix appropriate amounts of GeO2, Base, U-Acetate, and H2O in Teflon liner. Measure/record pH. Heat at given temperature for 7 days or stated time.

TABLE B.1 (CONTINUED)

Name GeO2 Base – LiOH H2O U Conc. pH Temperature Notes U-Nitrate UgeLi- 0.2216 1.35 not to be 6 g 0.2224 825 µL 0.0610 g 0.0614 mL 0.0900 12.21 150 redone UgeLi- 0.2216 1.35 7 g 0.2218 825 µL 0.1355 g 0.1356 mL 0.2000 12.04 - UgeLi- 0.2216 1.35 8 g 0.2211 825 µL 0.3389 g 0.3393 mL 0.5000 10.73 - UgeLi- 0.2216 1.35 9 g 0.2215 825 µL 0.6777 g 0.6774 mL 1.0000 3.39 - UgeLi- 0.2216 1.35 10 g 0.2217 825 µL 1.3554 g 1.3552 mL 2.0000 2.53 -

142 Name GeO2 Base – LiOH U-Acetate H2O U Conc. pH

0.1 M 4.24 M

UgeLi- 1350 1350 11 µL 825 µL 0.0540 g 0.0534 µL 0.0900 - 150 redone at 220 UgeLi- 1350 1350 12 µL 825 µL 0.1145 g 0.1147 µL 0.2000 - - UgeLi- 1350 1350 13 µL 825 µL 0.2862 g 0.2863 µL 0.5000 - - UgeLi- 1350 1350 14 µL 825 µL 0.5724 g 0.5726 µL 1.0000 - - UgeLi- 1350 1350 15 µL 825 µL 1.1448 g 1.1448 µL 2.0000 - -

TABLE B.1 (CONTINUED)

Name GeO2 Base – LiOH H2O U Conc. pH Temperature Notes U-Nitrate UgeLi- 1350 1350 16 µL 825 µL 0.0610 g 0.0614 µL 0.0900 - 150 redone at 220 UgeLi- 1350 1350 17 µL 825 µL 0.1355 g 0.1362 µL 0.2000 - - UgeLi- 1350 1350 18 µL 825 µL 0.3389 g 0.3390 µL 0.5000 - - UgeLi- 1350 1350 19 µL 825 µL 0.6777 g 0.6770 µL 1.0000 - - UgeLi- 1350 1350 20 µL 825 µL 1.3554 g 1.3560 µL 2.0000 - -

143 start here

Name GeO2 Base – LiOH U-Acetate H2O U Conc. pH w/pH

0.1 M 4.24 M light orange; UgeLi- 1350 1350 mostly powder 21 µL 825 µL 0.0540 g 0.0538 µL 0.0900 12.44 220 (2) TN orange; UgeLi- 1350 1350 fine powder 22 µL 825 µL 0.1145 g 0.1151 µL 0.2000 12.34 (2) UgeLi- 1350 1350 bright orange; 23 µL 825 µL 0.2862 g 0.2858 µL 0.5000 11.42 powder (2) UgeLi- 1350 1350 yellow; 24 µL 825 µL 0.5724 g 0.5725 µL 1.0000 11.30 clumpy

TABLE B.1 (CONTINUED)

Name GeO2 Base – LiOH H2O U Conc. pH Temperature Notes powder (2) UgeLi- 1350 1350 25 µL 825 µL 1.1448 g 1.1450 µL 2.0000 6.06 green; xtls (5)

U-Nitrate UgeLi- 1350 1350 pale yellow; 26 µL 825 µL 0.0610 g 0.0609 µL 0.0900 12.59 220 xtls (5) UgeLi- 1350 1350 light orange; 27 µL 825 µL 0.1355 g 0.1353 µL 0.2000 12.34 powder (2) UgeLi- 1350 1350 bright orange; 28 µL 825 µL 0.3389 g 0.3390 µL 0.5000 12.65 powder (2) UgeLi- 1350 1350 bright yellow;

144 29 µL 825 µL 0.6777 g 0.6771 µL 1.0000 8.00 xtls (5)

UgeLi- 1350 1350 bright yellow;

30 µL 825 µL 1.3554 g 1.3560 µL 2.0000 3.27 xtls (4)

Name GeO2 Base – LiOH U-Acetate H2O U Conc. pH 0.1 M 4.24 M ~6 220 UgeLi- 675 light yellow 31 675 µL 413 µL 0.0270 g 0.0268 µL 0.0900 5.96 powder UgeLi- 675 light yellow 32 675 µL 413 µL 0.0573 g 0.0578 µL 0.2000 5.91 powder brown/red UgeLi- 675 xtls and green 33 675 µL 413 µL 0.1431 g 0.1430 µL 0.5000 5.93 powder

TABLE B.1 (CONTINUED)

Name GeO2 Base – LiOH H2O U Conc. pH Temperature Notes yellow/brown UgeLi- 675 powder; some 34 675 µL 413 µL 0.2862 g 0.2867 µL 1.0000 6.08 xtls UgeLi- 675 yellow 35 675 µL 413 µL 0.5724 g 0.5725 µL 2.0000 5.94 powder; xtls

U-Nitrate ~3 220 UgeLi- 675 very small 36 675 µL 413 µL 0.0305 g 0.0303 µL 0.0900 3.06 yellow xtls UgeLi- 675 bright yellow 37 675 µL 413 µL 0.0678 g 0.0682 µL 0.2000 2.99 powder UgeLi- 675

145 38 675 µL 413 µL 0.1695 g 0.1688 µL 0.5000 3.09 yellow xtls UgeLi- 675 bright yellow 39 675 µL 413 µL 0.3389 g 0.3391 µL 1.0000 3.08 xtls; UO2(OH) UgeLi- 675 bright yellow 40 675 µL 413 µL 0.6777 g 0.6781 µL 2.0000 3.09 xtls; UO2(OH)

Name GeO2 Base – LiOH U-Acetate H2O U Conc. pH 220 0.05 M 4.24 M UgeLi- 675 41 675 µL 413 µL 0.5724 g µL 2.0000

U-Nitrate UGeLi- 675 µL 413 µL 0.6777 g 675 2.0000

TABLE B.1 (CONTINUED)

Name GeO2 Base – LiOH H2O U Conc. pH Temperature Notes

42 µL

146

TABLE B 2

POTASSIUM URANIUM GERMANATES*

Name GeO2 Base – KOH H2O U Conc. pH Temp Notes U-Acetate 4.24 M not to be UgeK-1 0.2216 g 825 µL 0.0540 g 1.35 mL 0.0900 13.45 150 redone UgeK-2 0.2216 g 825 µL 0.1145 g 1.35 mL 0.2000 13.30 -

147 UgeK-3 0.2216 g 825 µL 0.2862 g 1.35 mL 0.5000 13.07 - UgeK-4 0.2216 g 825 µL 0.5724 g 1.35 mL 1.0000 11.71 - UgeK-5 0.2216 g 825 µL 1.1448 g 1.35 mL 2.0000 6.51 - U-Nitrate not to be UgeK-6 0.2216 g 825 µL 0.0610 g 1.35 mL 0.0900 VOID 150 redone UgeK-7 0.2216 g 825 µL 0.1355 g 1.35 mL 0.2000 VOID - UgeK-8 0.2216 g 825 µL 0.3389 g 1.35 mL 0.5000 VOID - UgeK-9 0.2216 g 825 µL 0.6777 g 1.35 mL 1.0000 VOID - UgeK-10 0.2216 g 825 µL 1.3554 g 1.35 mL 2.0000 VOID -

* For each sample, mix appropriate amounts of GeO2, Base, U-Acetate, and H2O in Teflon liner. Measure/record pH. Heat at given temperature for 7 days or stated time.

TABLE B.2 (CONTINUED)

Name GeO2 Base – KOH H2O U Conc. pH Temp Notes 150-RT- redone at U-Acetate 190 220 0.1 M 4.24 M - Ugek-11 1350 µL 825 µL 0.0540 g 1350 µL 0.0900 13.92 Liquid Ugek-12 1350 µL 825 µL 0.1145 g 1350 µL 0.2000 13.61 Liquid Ugek-13 1350 µL 825 µL 0.2862 g 1350 µL 0.5000 13.58 floating xtls xtlline Ugek-14 1350 µL 825 µL 0.5724 g 1350 µL 1.0000 9.57 mass xtls; XRD

148 results: K U

Ugek-15 1350 µL 825 µL 1.1448 g 1350 µL 2.0000 5.69 Ac

U-Nitrate redone at Ugek-16 1350 µL 825 µL 0.0610 g 1350 µL 0.0900 14.05 190 220 Ugek-17 1350 µL 825 µL 0.1355 g 1350 µL 0.2000 13.91 - Ugek-18 1350 µL 825 µL 0.3389 g 1350 µL 0.5000 13.52 - Ugek-19 1350 µL 825 µL 0.6777 g 1350 µL 1.0000 3.99 - xtls;XRD results: new, Ugek-20 1350 µL 825 µL 1.3554 g 1350 µL 2.0000 3.12 twinned

TABLE B.2 (CONTINUED)

Name GeO2 Base – KOH H2O U Conc. pH Temp Notes start here Name GeO2 Base – KOH U-Acetate H2O U Conc. pH w/pH 0.1 M 4.24 M 220 light orange; Ugek-21 1350 µL 825 µL 0.0540 g 1350 µL 0.0900 13.58 powder (2) 150-RT- redone at Name GeO2 Base – KOH U-Acetate H2O U Conc. pH 190 220 TN orange; clumpy Ugek-22 1350 µL 825 µL 0.1145 g 1350 µL 0.2000 13.35 powder (2)

149 bright orange; clumpy Ugek-23 1350 µL 825 µL 0.2862 g 1350 µL 0.5000 13.31 powder (2) green; flaky Ugek-24 1350 µL 825 µL 0.5724 g 1350 µL 1.0000 11.02 powder (1) green; flaky Ugek-25 1350 µL 825 µL 1.1448 g 1350 µL 2.0000 10.37 powder (1)

U-Nitrate yellow; xtls Ugek-26 1350 µL 825 µL 0.0610 g 1350 µL 0.0900 13.40 (5) TN orange; Ugek-27 1350 µL 825 µL 0.1355 g 1350 µL 0.2000 13.18 powder (2)

TABLE B.2 (CONTINUED)

Name GeO2 Base – KOH H2O U Conc. pH Temp Notes bright orange; clumpy Ugek-28 1350 µL 825 µL 0.3389 g 1350 µL 0.5000 12.90 powder (2) bright orange; xtls Ugek-29 1350 µL 825 µL 0.6777 g 1350 µL 1.0000 3.29 (5) yellow and Ugek-30 1350 µL 825 µL 1.3554 g 1350 µL 2.0000 3.13 orange; xtls

Name GeO2 Base – KOH U-Acetate H2O U Conc. pH

150 0.1 M 4.24 M ~6 220

not enough

powder Ugek-32 635 µL 413 µL 0.0573 g 635 µL 0.2000 5.58 present dark green Ugek-33 635 µL 413 µL 0.1431 g 635 µL 0.5000 6.06 powder dark green Ugek-34 635 µL 413 µL 0.2862 g 635 µL 1.0000 6.13 powder black Ugek-35 635 µL 413 µL 0.5724 g 635 µL 2.0000 5.91 powder

U-Nitrate ~3 220 light yellow Ugek-36 635 µL 413 µL 0.0305 g 635 µL 0.0900 3.09 powder

TABLE B.2 (CONTINUED)

Name GeO2 Base – KOH H2O U Conc. pH Temp Notes light yellow Ugek-37 635 µL 413 µL 0.0678 g 635 µL 0.2000 2.94 powder light yellow Ugek-38 635 µL 413 µL 0.1695 g 635 µL 0.5000 3.08 powder orange xtls with Ugek-39 635 µL 413 µL 0.3389 g 635 µL 1.0000 3.03 powder charcoal gray Ugek-40 635 µL 413 µL 0.6777 g 635 µL 2.0000 2.9 powder

151

TABLE B 3

SODIUM URANIUM GERMANATES*

Base – Name GeO2 NaOH U-Acetate H2O U Conc. pH Temp/Duration Notes 4.24 M Record 220/7 days UGeNa-1 675 µL 413 µL 0.0270 g 675 µL 0.0900 14.29 yellow powder UGeNa-2 675 µL 413 µL 0.0573 g 675 µL 0.2000 13.08 yellow powder UGeNa-3 675 µL 413 µL 0.1431 g 675 µL 0.5000 12.95 orange powder

UGeNa-4 675 µL 413 µL 0.2862 g 675 µL 1.0000 12.05 left in a day longer mustard yellow powder 15

UGeNa-5 675 µL 413 µL 0.5724 g 675 µL 2.0000 7.41 left in a day longer greenish-yellow powder 2

U-Nitrate UGeNa-6 675 µL 413 µL 0.0305 g 675 µL 0.0900 14.37 light yellow powder UGeNa-7 675 µL 413 µL 0.0678 g 675 µL 0.2000 13.36 UGeNa-8 675 µL 413 µL 0.1695 g 675 µL 0.5000 11.81 orange powder UGeNa-9 675 µL 413 µL 0.3389 g 675 µL 1.0000 7.56 bright yellow powder yellow powder with UGeNa-10 675 µL 413 µL 0.6777 g 675 µL 2.0000 2.62 yellow xtls

* For each sample, mix appropriate amounts of GeO2, Base, U-Acetate, and H2O in Teflon liner. Measure/record pH. Heat at given temperature for 7 days or stated time.

TABLE B 4

RUBIDIUM URANIUM GERMANATES*

Base – Name GeO2 NaOH U-Acetate H2O U Conc. pH Temp/Duration Notes 4.24 M Record 220/7 days parr bomb can't be UGeRb-1 675 µL 413 µL 0.0270 g 675 µL 0.0900 14.4 opened (14) UGeRb-2 675 µL 413 µL 0.0573 g 675 µL 0.2000 13.81 yellow powder UGeRb-3 675 µL 413 µL 0.1431 g 675 µL 0.5000 13.96 orange powder UGeRb-4 675 µL 413 µL 0.2862 g 675 µL 1.0000 13.33 yellow powde UGeRb-5 675 µL 413 µL 0.5724 g 675 µL 2.0000 6.26 army green powder

153

U-Nitrate

UGeRb-6 675 µL 413 µL 0.0305 g 675 µL 0.0900 14.03 yellow powder UGeRb-7 675 µL 413 µL 0.0678 g 675 µL 0.2000 13.4 bright yellow powder UGeRb-8 675 µL 413 µL 0.1695 g 675 µL 0.5000 13.24 yellow powder UGeRb-9 675 µL 413 µL 0.3389 g 675 µL 1.0000 11.1 yellow powder orange/red/yellow xtls UGeRb-10 675 µL 413 µL 0.6777 g 675 µL 2.0000 3.04 in orange powder matrix

* For each sample, mix appropriate amounts of GeO2, Base, U-Acetate, and H2O in Teflon liner. Measure/record pH. Heat at given temperature for 7 days or stated time.

TABLE B 5

CESIUM URANIUM GERMANATES*

Base – Name GeO2 CsOH U-Acetate H2O U Conc. pH Temp/Duration Notes 0.1 M 4.24 M Record 220/7 days UGeCs-1 675 µL 413 µL 0.0270 g 675 µL 0.0900 13.95 rectangular orange xtls UGeCs-2 675 µL 413 µL 0.0573 g 675 µL 0.2000 13.43 rectangular orange xtls UGeCs-3 675 µL 413 µL 0.1431 g 675 µL 0.5000 13.58 orange/yellow xtls 154 yellow-green powder with

UGeCs-4 675 µL 413 µL 0.2862 g 675 µL 1.0000 7.07 small fibrous xtls cooled slowly; UGeCs-4a 675 µL 413 µL 0.2862 g 675 µL 1.0000 7.25 oven turned off UGeCs-5 675 µL 413 µL 0.5724 g 675 µL 2.0000 5.73 dark green powder U-Nitrate UGeCs-6 675 µL 413 µL 0.0305 g 675 µL 0.0900 13.97 rectangular orange xtls

* For each sample, mix appropriate amounts of GeO2, Base, U-Acetate, and H2O in Teflon liner. Measure/record pH. Heat at given temperature for 7 days or stated time.

TABLE B 5 (CONTINUED)

Base – Name GeO2 CsOH U-Acetate H2O U Conc. pH Temp/Duration Notes UGeCs-7 675 µL 413 µL 0.0678 g 675 µL 0.2000 12.8 rectangular orange xtls UGeCs-8 675 µL 413 µL 0.1695 g 675 µL 0.5000 13.07 UGeCs-9 675 µL 413 µL 0.3389 g 675 µL 1.0000 4.26 UGeCs-10 675 µL 413 µL 0.6777 g 675 µL 2.0000 2.61

155

TABLE B 6

AMMONIUM URANIUM GERMANATES*

Base – Name GeO2 (NH4)OH U-Acetate H2O U Conc. pH Temp/Duration Notes 0.1 M 4.24 M Record 220/7 days UGeAmm-1 675 µL 413 µL 0.0270 g 675 µL 0.0900 10.72 grey powder UGeAmm-2 675 µL 413 µL 0.0573 g 675 µL 0.2000 10.42 light green powder UGeAmm-3 675 µL 413 µL 0.1431 g 675 µL 0.5000 10.05 UGeAmm-4 675 µL 413 µL 0.2862 g 675 µL 1.0000 9.77 UGeAmm-5 675 µL 413 µL 0.5724 g 675 µL 2.0000 8.27 green-gray powder

156 U-Nitrate UGeAmm-6 675 µL 413 µL 0.0305 g 675 µL 0.0900 10.38 orange powder UGeAmm-7 675 µL 413 µL 0.0678 g 675 µL 0.2000 10.13 light yellow powder UGeAmm-8 675 µL 413 µL 0.1695 g 675 µL 0.5000 10.39 orange xtls with red UGeAmm-9 675 µL 413 µL 0.3389 g 675 µL 1.0000 9.75 hexagonal xtls UGeAmm-10 675 µL 413 µL 0.6777 g 675 µL 2.0000 4.23 orange blady xtls

* For each sample, mix appropriate amounts of GeO2, Base, U-Acetate, and H2O in Teflon liner. Measure/record pH. Heat at given temperature for 7 days or stated time.

TABLE B 7

MAGNESIUM URANIUM GERMANATES*

Base – GeO2 Mg(OH)2 U-Acetate H2O U Conc. pH Temp/Duration Notes Name 0.1 M 4.24 M Record 220/7 days UGeMg-1 675 µL 413 µL 0.0270 g 675 µL 0.0900 5.16 yellow powder UGeMg-2 675 µL 413 µL 0.0573 g 675 µL 0.2000 4.56 UGeMg-3 675 µL 413 µL 0.1431 g 675 µL 0.5000 4.31 yellow powder UGeMg-4 675 µL 413 µL 0.2862 g 675 µL 1.0000 4.7 yellow powder UGeMg-5 675 µL 413 µL 0.5724 g 675 µL 2.0000 4.3

157 U-Nitrate UGeMg-6 675 µL 413 µL 0.0305 g 675 µL 0.0900 4.69 UGeMg-7 675 µL 413 µL 0.0678 g 675 µL 0.2000 3.94 UGeMg-8 675 µL 413 µL 0.1695 g 675 µL 0.5000 3.68 UGeMg-9 675 µL 413 µL 0.3389 g 675 µL 1.0000 3.3 UGeMg-10 675 µL 413 µL 0.6777 g 675 µL 2.0000 4.15

* For each sample, mix appropriate amounts of GeO2, Base, U-Acetate, and H2O in Teflon liner. Measure/record pH. Heat at given temperature for 7 days or stated time.

TABLE B 8

CALCIUM URANIUM GERMANATES*

Base – Name GeO2 Ca(OH)2 U-Acetate H2O U Conc. pH Temp/Duration Notes 0.1 M 4.24 M Record 220/7 days UGeCa-1 675 µL 413 µL 0.0270 g 675 µL 0.0900 10.94 yellow powder UGeCa-2 675 µL 413 µL 0.0573 g 675 µL 0.2000 11.53 yellow powder UGeCa-3 675 µL 413 µL 0.1431 g 675 µL 0.5000 11.98 yellow powder UGeCa-4 675 µL 413 µL 0.2862 g 675 µL 1.0000 11.07 green powder UGeCa-5 675 µL 413 µL 0.5724 g 675 µL 2.0000 10.98 green powder

158 U-Nitrate orange-yellow UGeCa-6 675 µL 413 µL 0.0305 g 675 µL 0.0900 12.02 powder UGeCa-7 675 µL 413 µL 0.0678 g 675 µL 0.2000 10.85 UGeCa-8 675 µL 413 µL 0.1695 g 675 µL 0.5000 10.97 UGeCa-9 675 µL 413 µL 0.3389 g 675 µL 1.0000 11.61 UGeCa-10 675 µL 413 µL 0.6777 g 675 µL 2.0000 7.56

* For each sample, mix appropriate amounts of GeO2, Base, U-Acetate, and H2O in Teflon liner. Measure/record pH. Heat at given temperature for 7 days or stated time.

TABLE B 9

STRONTIUM URANIUM GERMANATES*

Base – Name GeO2 Sr(OH)2 U-Acetate H2O U Conc. pH Temp/Duration Notes 0.1 M 2.12 M Record 220/7 days UGeSr-1 675 µL 413 µL 0.0270 g 675 µL 0.0900 5.88 UGeSr-2 675 µL 413 µL 0.0573 g 675 µL 0.2000 5 UGeSr-3 675 µL 413 µL 0.1431 g 675 µL 0.5000 5.41 UGeSr-4 675 µL 413 µL 0.2862 g 675 µL 1.0000 5.11 UGeSr-5 675 µL 413 µL 0.5724 g 675 µL 2.0000 3.76

159 U-Nitrate UGeSr-6 675 µL 413 µL 0.0305 g 675 µL 0.0900 4.11 UGeSr-7 675 µL 413 µL 0.0678 g 675 µL 0.2000 3.65 UGeSr-8 675 µL 413 µL 0.1695 g 675 µL 0.5000 2.91 UGeSr-9 675 µL 413 µL 0.3389 g 675 µL 1.0000 1.97 UGeSr-10 675 µL 413 µL 0.6777 g 675 µL 2.0000 1.77

* For each sample, mix appropriate amounts of GeO2, Base, U-Acetate, and H2O in Teflon liner. Measure/record pH. Heat at given temperature for 7 days or stated time.

TABLE B 10

BARIUM URANIUM GERMANATES: *

Base – Name GeO2 Ba(OH)2 U-Acetate H2O U Conc. pH Temp/Duration Notes 0.1 M .25 M Record 220/7 days UGeBa-1 675 µL 413 µL 0.0270 g 675 µL 0.0900 10.76 UGeBa-2 675 µL 413 µL 0.0573 g 675 µL 0.2000 5.57 UGeBa-3 675 µL 413 µL 0.1431 g 675 µL 0.5000 5.15 UGeBa-4 675 µL 413 µL 0.2862 g 675 µL 1.0000 4.74 UGeBa-5 675 µL 413 µL 0.5724 g 675 µL 2.0000 3.83

160 U-Nitrate UGeBa-6 675 µL 413 µL 0.0305 g 675 µL 0.0900 11.52 UGeBa-7 675 µL 413 µL 0.0678 g 675 µL 0.2000 4.02 red/orange xtls UGeBa-8 675 µL 413 µL 0.1695 g 675 µL 0.5000 2.93 UGeBa-9 675 µL 413 µL 0.3389 g 675 µL 1.0000 2.3 UGeBa-10 675 µL 413 µL 0.6777 g 675 µL 2.0000 2.24

* For each sample, mix appropriate amounts of GeO2, Base, U-Acetate, and H2O in Teflon liner. Measure/record pH. Heat at given temperature for 7 days or stated time.

TABLE B 11

MIXED BASED URANIUM GERMANATES*

Base – 206 Name GeO2 µL/ea U-Acetate H2O U Conc. pH Temperature Notes 0.1 M 4.24 M MB_1 675 µL LiOH/KOH 0.0270 g 675 µL 0.0900 12.42 220 MB_2 675 µL LiOH/KOH 0.0573 g 675 µL 0.2000 11.61 220 MB_3 675 µL LiOH/KOH 0.1431 g 675 µL 0.5000 12.52 220 MB_4 675 µL LiOH/KOH 0.2862 g 675 µL 1.0000 12.4 220 MB_5 675 µL LiOH/KOH 0.5724 g 675 µL 2.0000 6.96 220

161 MB_6 675 µL LiOH/NaOH 0.0270 g 675 µL 0.0900 13.06 220 MB_7 675 µL LiOH/NaOH 0.0573 g 675 µL 0.2000 12.89 220 MB_8 675 µL LiOH/NaOH 0.1431 g 675 µL 0.5000 12.61 220 MB_9 675 µL LiOH/NaOH 0.2862 g 675 µL 1.0000 12.47 220 MB_10 675 µL LiOH/NaOH 0.5724 g 675 µL 2.0000 6.46 220

MB_11 675 µL LiOH/RbOH 0.0270 g 675 µL 0.0900 13.13 220 MB_12 675 µL LiOH/RbOH 0.0573 g 675 µL 0.2000 13.13 220 MB_13 675 µL LiOH/RbOH 0.1431 g 675 µL 0.5000 12.73 220

* For each sample, mix appropriate amounts of GeO2, Base, U-Acetate, and H2O in Teflon liner. Measure/record pH. Heat at given temperature for 7 days or stated time.

TABLE B 11 (CONTINUED)

Base – 206 Name GeO2 µL/ea U-Acetate H2O U Conc. pH Temperature Notes MB_14 675 µL LiOH/RbOH 0.2862 g 675 µL 1.0000 11.79 220 MB_15 675 µL LiOH/RbOH 0.5724 g 675 µL 2.0000 6.34 220

MB_16 675 µL LiOH/CsOH 0.0270 g 675 µL 0.0900 12.89 220 MB_17 675 µL LiOH/CsOH 0.0573 g 675 µL 0.2000 12.65 220 MB_18 675 µL LiOH/CsOH 0.1431 g 675 µL 0.5000 12.40 220 MB_19 675 µL LiOH/CsOH 0.2862 g 675 µL 1.0000 9.24 220 MB_20 675 µL LiOH/CsOH 0.5724 g 675 µL 2.0000 5.34 220

162

TABLE B 12

DESCRIPTION OF SELECTED URANIUM GERMANATE MATERIALS.

Scan alpha/beta Space Sample Description Date XRD Time a/b/c /gamma Group Results Formula

Lithium

163 red/black

needle; other Beta-U3O8; xtl types to be 7.11/11.3 different space Ugeli_25 XRD'd 3/27/2009 20 sec 4/15.24 90/90/90 Immm group B-U3O8 yellow, hexagonal; need a new UGeLi_33 xtl 4/8/2009 10 sec poor crystal large yellow Cmca UGeLi_40 crystals 4/7/2009 (#64) alpha-UO2 UO2(OH) known structure; yellow, diuranyl blocky; good 8.18/11.5 Fddd germanate (UO2)2GeO UGeLi_38 spots 4/8/2009 10 sec 0/19.35 90/90/90 (#70) dihydrate 4(H2O)2 UGeLi_39 yellow 4/8/2009 10 sec 4.22/10.3 90/90/90 Cmca known structure; UO2(OH)

TABLE B 12 (CONTINUED)

Scan alpha/beta Space Sample Description Date XRD Time a/b/c /gamma Group Results Formula

3/6.87 (#64) alpha-UO2 large, clear, 8.36/4.97 90/114.67/ C12/C1 known structure; UGeLi_26clear blocky xtl 4/13/2009 10 sec /6.19 90 (#15) Li2(CO3) red intergrown plates Li3[(UO6)2 (hexagonal); 10.27/10. P-31c (UO2)9(Ge UGeLi_29red IR 4/13/2009 30 sec 27/17.06 90/90/120 (#163) p-31c.ins; solved O4)2(OH)] red hexagonal 164 crystal (xrd

and SEM 10/10/20 P-31c no change from LiRb-1 done) 8/18/2009 10 sec 17 90/90/120 (#163) original crystal

Potassium 14.37/14. Ugek_15 yellow blades 2/17/2009 37/26.32 K U Acetate Ugek_20 need new xtl twinned orange intergrown plates peter.ins; K[(UO6)2( Ugek_30orang (hexagonal); 10.22/10. P-31c disorder in Ge; UO2)9(Ge2 e IR 2/26/2009 60 sec 22/17.15 90/90/120 (#163) partially solved O7)(OH)] Ugek_30yellow yellow 2/26/2009 twinned

TABLE B 12 (CONTINUED)

Scan alpha/beta Space Sample Description Date XRD Time a/b/c /gamma Group Results Formula

blades; need new xtl refinement not good; new xtl needed; K version bright of known orange; structure twinned (NH4)3((UO2)10 blades; IR; 11.67/21. 90/103.86/ O10(OH))((UO4)( UGek_29 need new xtl 4/15/2009 10 sec 25/14.78 90 C2/c H2O)2)(H2O)2 165 large blocky

fibers; white and black under normal 6.9/19.5/ K[(UO2)5O MB_5 light 9/30/2009 10 sec 7.2 Pbam known structure 8](UO2)2

Rubidium yellow xtls and orange polycrystallin 4.3/6.9/1 UGeRb_10 e balls 5/22/2009 10 sec 0.2 uranyl hydroxide

Cesium UGeCs_7 orange 5/22/2009 10 sec 14.5/4.3/ di-cesium di- similar xtls

TABLE B 12 (CONTINUED)

Scan alpha/beta Space Sample Description Date XRD Time a/b/c /gamma Group Results Formula

rectangular 7.6 uranate present in UGeCs_3 and _6 known structure, red 11.4/11.4 Keriann found in UGeCs_10 trapezoidal 6/8/2009 10 sec /43.7 90/90/120 2006 w/o Ge small xtls; poor refinement; new xtls to 166 7.62/4.22 be

UgeCs_4 6/11/2009 30 sec /11.17 90/93.3/90 synthesized yellow blades in yellow 8.7/7.01/ 90/102.6/9 twinned; not UgeCs_4a powder 7/6/2009 30 sec 10.52 0 solved

Ammonium red hexagonal p-31c.ins; new formula to UGeAmm-10 xtls 6/19/2009 30 sec P-31c struct.; solved be revised red hexagonal 10.24/10. no change from AmmLi_1 xtls 9/18/2009 10 sec 26/17.35 90/90/120 P-31c original syn

TABLE B 12 (CONTINUED)

Scan alpha/beta Space Sample Description Date XRD Time a/b/c /gamma Group Results Formula

red hexagonal 10.24/10. no change from AmmK_1 xtls 9/19/2009 10 sec 24/17.35 90/90/120 P-31c original syn

Strontium orange xtls; irregular UGeSr_5o blocky 7/7/2009 10 sec poor unit

cell 167 large selection;

yellow/green twinned; not new xtls UGeSr_5y crystals 7/7/2009 10 sec solved needed

Barium orange hexagonal plates in silky yellow fibrous 10.23/10. formula to UGeBa_7 matrix; IR 7/27/2009 20 sec 23/17.21 90/90/120 P-31c solved be added

Calcium UGeCa_10 yellow fiber 9/30/2009 10

TABLE B 12 (CONTINUED)

Scan alpha/beta Space Sample Description Date XRD Time a/b/c /gamma Group Results Formula

sec.

168

TABLE B 13

CESIUM URANIUM NITRATE GERMANATES*

GeO2 U-Nitrate CsNO3 RbNO3 H2O Sample (g) Actual (g) Actual (g) (g) Actual (mL) Ge:U:M+ (M) pH Ge_CsN_X 0.0609 0.0612 0.0879 0.0878 0.4451 - 0.4451 3 1:.3:4 2.63 Ge_CsN_1_4 0.0183 0.0183 0.0879 0.0881 0.4540 - 0.4543 3 1:1:4 2.78 Ge_CsN_2_4 0.0183 0.0187 0.1758 0.1758 0.4540 - 0.4538 3 1:2:4 2.47 Ge_CsN_3_4 0.0183 0.0188 0.2637 0.2644 0.4540 - 0.4543 3 1:3:4 2.26 Ge_CsN_4_4 0.0183 0.0183 0.3516 0.3522 0.4540 - 0.4538 3 1:4:4 1.98

169 Ge_CsN_5_4 0.0183 0.0185 0.4395 0.4397 0.4540 - 0.4542 3 1:5:4 1.97 Ge_CsN_6_4 0.0183 0.0187 0.5274 0.5274 0.4540 - 0.4546 3 1:6:4 1.88 Ge_CsN_7_4 0.0183 0.0183 0.6153 0.6156 0.4540 - 0.4547 3 1:7:4 1.87 Ge_CsN_8_4 0.0183 0.0182 0.7032 0.7033 0.4540 - 0.4547 3 1:8:4 1.71 Ge_CsN_9_4 0.0183 0.0186 0.7911 0.7914 0.4540 - 0.4545 3 1:9:4 1.68 Ge_CsN_10_4 0.0183 0.0187 0.8790 0.8795 0.4540 - 0.4544 3 1:10:4 1.63

Ge_CsN_1_1 0.0183 0.0187 0.0879 0.0881 0.1135 - 0.1139 3 1:1:1 2.7 Ge_CsN_2_1 0.0183 0.0186 0.1758 0.176 0.1135 - 0.1141 3 1:2:1 2.43 Ge_CsN_3_1 0.0183 0.0185 0.2637 0.2639 0.1135 - 0.1134 3 1:3:1 2.21

* For each sample, mix appropriate amounts of GeO2, U-Nitrate, Cs/RBNO3, and H2O in a glass test tube. Measure/record pH. Transfer slurry/solution to Teflon liner. Heat at 220ºC for 7 days.

TABLE B 13 (CONTINUED)

GeO2 U-Nitrate CsNO3 RbNO3 H2O Ge:U:M+ Sample (g) Actual (g) Actual (g) (g) Actual (mL) (M) pH Ge_CsN_4_1 0.0183 0.0187 0.3516 0.3519 0.1135 - 0.1136 3 1:4:1 1.97 Ge_CsN_5_1 0.0183 0.0185 0.4395 0.4393 0.1135 - 0.1136 3 1:5:1 1.87 Ge_CsN_6_1 0.0183 0.0184 0.5274 0.5274 0.1135 - 0.1134 3 1:6:1 1.65 Ge_CsN_7_1 0.0183 0.0185 0.6153 0.6154 0.1135 - 0.114 3 1:7:1 1.71 Ge_CsN_8_1 0.0183 0.0186 0.7032 0.7032 0.1135 - 0.114 3 1:8:1 1.75 Ge_CsN_9_1 0.0183 0.0184 0.7911 0.7918 0.1135 - 0.1139 3 1:9:1 1.71 Ge_CsN_10_1 0.0183 0.0186 0.8790 0.8791 0.1135 - 0.1139 3 1:10:1 1.54

Ge_CsN_1_2 0.0183 NR 0.0879 0.0884 0.2270 - 0.2272 3 1:1:2 2.28 Ge_CsN_2_2 0.0183 NR 0.1758 0.1762 0.2270 - 0.2274 3 1:2:2 2.06 170 Ge_CsN_3_2 0.0183 NR 0.2637 0.2676 0.2270 - 0.2271 3 1:3:2 1.92

Ge_CsN_4_2 0.0183 NR 0.3516 0.352 0.2270 - 0.2271 3 1:4:2 1.82 Ge_CsN_5_2 0.0183 NR 0.4395 0.4395 0.2270 - 0.2274 3 1:5:2 1.68 Ge_CsN_6_2 0.0183 NR 0.5274 0.5271 0.2270 - 0.2276 3 1:6:2 1.88 Ge_CsN_7_2 0.0183 NR 0.6153 0.6151 0.2270 - 0.2275 3 1:7:2 1.83 Ge_CsN_8_2 0.0183 NR 0.7032 0.7036 0.2270 - 0.2277 3 1:8:2 1.66 Ge_CsN_9_2 0.0183 NR 0.7911 0.7913 0.2270 - 0.2272 3 1:9:2 1.66 Ge_CsN_10_2 0.0183 NR 0.8790 0.8793 0.2270 - 0.227 3 1:10:2 1.6

Ge_CsN_1_3 0.0183 NR 0.0879 0.0882 0.3405 - NR 3 1:1:3 2.26 Ge_CsN_2_3 0.0183 NR 0.1758 0.1761 0.3405 - NR 3 1:2:3 1.99 Ge_CsN_3_3 0.0183 NR 0.2637 0.2635 0.3405 - NR 3 1:3:3 1.8 Ge_CsN_4_3 0.0183 NR 0.3516 0.3522 0.3405 - NR 3 1:4:3 1.66 Ge_CsN_5_3 0.0183 NR 0.4395 0.4398 0.3405 - NR 3 1:5:3 1.48 Ge_CsN_6_3 0.0183 NR 0.5274 0.5279 0.3405 - 0.3407 3 1:6:3 1.66

TABLE B 13 (CONTINUED)

GeO2 U-Nitrate CsNO3 RbNO3 H2O Ge:U:M+ Sample (g) Actual (g) Actual (g) (g) Actual (mL) (M) pH Ge_CsN_7_3 0.0183 NR 0.6153 0.6152 0.3405 - 0.3404 3 1:7:3 1.64 Ge_CsN_8_3 0.0183 NR 0.7032 0.703 0.3405 - 0.3406 3 1:8:3 1.61 Ge_CsN_9_3 0.0183 NR 0.7911 0.7911 0.3405 - 0.3405 3 1:9:3 1.58 Ge_CsN_10_3 0.0183 NR 0.8790 0.8798 0.3405 - 0.3404 3 1:10:3 1.51

171

TABLE B 14

DESCRIPTION OF SELECTED MATERIALS.

Sample Description Ge_CsN_X - Ge_CsN_1_4 - Ge_CsN_2_4 - Ge_CsN_3_4 - Ge_CsN_4_4 -

172 Ge_CsN_5_4 - Ge_CsN_6_4 - Ge_CsN_7_4 - Ge_CsN_8_4 - Ge_CsN_9_4 - Ge_CsN_10_4 -

Ge_CsN_1_1 - Ge_CsN_2_1 - Ge_CsN_3_1 - Ge_CsN_4_1 - Ge_CsN_5_1 - Ge_CsN_6_1 two crystal types: larger pale yellow & smaller, cubic orange/red Ge_CsN_7_1 - Ge_CsN_8_1 -

TABLE B.14 (CONTINUED)

Sample Description

Ge_CsN_9_1 - Ge_CsN_10_1 -

Ge_CsN_1_2 - Ge_CsN_2_2 - Ge_CsN_3_2 - Ge_CsN_4_2 - Ge_CsN_5_2 - Ge_CsN_6_2 few small clear crystals in pale powder Ge_CsN_7_2 powder 173 Ge_CsN_8_2 urchin-like balls, spherical, powder

Ge_CsN_9_2 powder, spiny fibers Ge_CsN_10_2 clumps of pale yellow powder, some black specks

Ge_CsN_1_3 - Ge_CsN_2_3 - Ge_CsN_3_3 - Ge_CsN_4_3 - Ge_CsN_5_3 - Ge_CsN_6_3 - Ge_CsN_7_3 - Ge_CsN_8_3 - Ge_CsN_9_3 - Ge_CsN_10_3 -

TABLE B 15

RUBIDIUM URANIUM NITRATE GERMANATES*

GeO2 U-Nitrate CsNO3 RbNO3 H2O Sample (g) Actual (g) Actual (g) (g) Actual (mL) Ge:U:M+ (M) pH Ge_RbN_X 0.0230 0.0232 0.0773 0.0775 - 0.3350 0.3352 3 1:.7:10 2.78 Ge_RbN_1_10 0.0161 0.0967 0.0773 0.0745 - 0.3242 0.3544 3 1:1:10 NR 174 Ge_RbN_2_10 0.0161 0.0967 0.1546 0.1545 - 0.3242 0.3547 3 1:2:10 NR

Ge_RbN_3_10 0.0161 0.0967 0.2319 0.2321 - 0.3242 0.3544 3 1:3:10 NR Ge_RbN_4_10 0.0161 0.0967 0.3092 0.3092 - 0.3242 0.3541 3 1:4:10 NR Ge_RbN_5_10 0.0161 0.0967 0.3865 0.3864 - 0.3242 0.3545 3 1:5:10 NR Ge_RbN_6_10 0.0161 0.097 0.4638 0.4637 - 0.3242 0.4451 3 1:6:10 1.53 Ge_RbN_7_10 0.0161 0.097 0.5411 0.5414 - 0.3242 0.4451 3 1:7:10 1.52 Ge_RbN_8_10 0.0161 0.097 0.6184 0.6183 - 0.3242 0.4451 3 1:8:10 1.42 Ge_RbN_9_10 0.0161 0.097 0.6957 0.6957 - 0.3242 0.4451 3 1:9:10 1.43 Ge_RbN_10_10 0.0161 0.097 0.7730 0.7729 - 0.3242 0.4451 3 1:10:10 1.31

Ge_RbN_1_7 0.0161 0.0159 0.0773 0.0772 - 0.2269 0.2265 3 1:1:7 2.73

* For each sample, mix appropriate amounts of GeO2, U-Nitrate, Cs/RBNO3, and H2O in a glass test tube. Measure/record pH. Transfer slurry/solution to Teflon liner. Heat at 220ºC for 7 days.

TABLE B.15 (CONTINUED)

GeO2 U-Nitrate CsNO3 RbNO3 H2O Sample (g) Actual (g) Actual (g) (g) Actual (mL) Ge:U:M+ (M) pH Ge_RbN_2_7 0.0161 0.0163 0.1546 0.1547 - 0.2269 0.2271 3 1:2:7 2.51 Ge_RbN_3_7 0.0161 0.0162 0.2319 0.2321 - 0.2269 0.2268 3 1:3:7 2.31 Ge_RbN_4_7 0.0161 0.0157 0.3092 0.3088 - 0.2269 0.2266 3 1:4:7 2.25 Ge_RbN_5_7 0.0161 0.016 0.3865 0.3869 - 0.2269 0.2268 3 1:5:7 2.17 Ge_RbN_6_7 0.0161 0.0158 0.4638 0.4633 - 0.2269 0.2271 3 1:6:7 2.11 Ge_RbN_7_7 0.0161 0.0163 0.5411 0.541 - 0.2269 0.2273 3 1:7:7 2.07 Ge_RbN_8_7 0.0161 0.0162 0.6184 0.6182 - 0.2269 0.2274 3 1:8:7 1.99 Ge_RbN_9_7 0.0161 0.0159 0.6957 0.6957 - 0.2269 0.2267 3 1:9:7 1.98 Ge_RbN_10_7 0.0161 0.0165 0.7730 0.7735 - 0.2269 0.2265 3 1:10:7 1.91

Ge_RbN_1_8 0.0161 0.0158 0.0773 0.0772 - 0.2594 0.2589 3 1:1:8 2.97

Ge_RbN_2_8 0.0161 0.0165 0.1546 0.1547 - 0.2594 0.2594 3 1:2:8 2.81 175 Ge_RbN_3_8 0.0161 0.0164 0.2319 0.2315 - 0.2594 0.2597 3 1:3:8 2.6 Ge_RbN_4_8 0.0161 0.0157 0.3092 0.3088 - 0.2594 0.2592 3 1:4:8 2.53 Ge_RbN_5_8 0.0161 0.0158 0.3865 0.387 - 0.2594 0.259 3 1:5:8 2.49 Ge_RbN_6_8 0.0161 0.0168 0.4638 0.4634 - 0.2594 0.259 3 1:6:8 2.36 Ge_RbN_7_8 0.0161 0.0157 0.5411 0.5405 - 0.2594 0.259 3 1:7:8 2.32 Ge_RbN_8_8 0.0161 0.0164 0.6184 0.6186 - 0.2594 0.259 3 1:8:8 2.31 Ge_RbN_9_8 0.0161 0.0164 0.6957 0.6955 - 0.2594 0.2596 3 1:9:8 2.18 Ge_RbN_10_8 0.0161 0.0157 0.7730 0.7729 - 0.2594 0.2596 3 1:10:8 2.15

Ge_RbN_1_9 0.0161 0.0163 0.0773 0.0775 - 0.2918 0.2918 3 1:1:9 3.35 Ge_RbN_2_9 0.0161 0.0156 0.1546 0.1546 - 0.2918 0.2919 3 1:2:9 3.15 Ge_RbN_3_9 0.0161 0.0163 0.2319 0.2319 - 0.2918 0.2921 3 1:3:9 3.03 Ge_RbN_4_9 0.0161 0.0164 0.3092 0.3097 - 0.2918 0.2923 3 1:4:9 2.96 Ge_RbN_5_9 0.0161 0.0165 0.3865 0.3869 - 0.2918 0.2918 3 1:5:9 2.85

TABLE B.15 (CONTINUED)

GeO2 U-Nitrate CsNO3 RbNO3 H2O Sample (g) Actual (g) Actual (g) (g) Actual (mL) Ge:U:M+ (M) pH Ge_RbN_6_9 0.0161 0.0164 0.4638 0.4636 - 0.2918 0.2919 3 1:6:9 2.74 Ge_RbN_7_9 0.0161 0.0165 0.5411 0.541 - 0.2918 0.2919 3 1:7:9 2.68 Ge_RbN_8_9 0.0161 0.0164 0.6184 0.6186 - 0.2918 0.292 3 1:8:9 2.58 Ge_RbN_9_9 0.0161 0.0164 0.6957 0.6953 - 0.2918 0.2918 3 1:9:9 2.56 Ge_RbN_10_9 0.0161 0.0162 0.7730 0.7727 - 0.2918 0.292 3 1:10:9 2.44

176

TABLE B 16

URANIUM GERMANATES*

Molarity Volume Sample U-Nitrate soln

# Ge U Ratio GeO2 soln (µL) (µL) pH Date/Notes Ge_1 0.01 0.01 1:1 100 100 NR yellow powder

177 Ge_2 0.02 0.01 2:1 200 100 3.24 yellow/orange powder

small, blocky yellow

Ge_3 0.03 0.01 3:1 300 100 3.28 xtls Ge_4 0.04 0.01 4:1 400 100 3.3 pale, yellow fibers Ge_5 0.05 0.01 5:1 500 100 3.43 yellow, blocky xtls Ge_6 0.06 0.01 6:1 600 100 3.54 no visible products Ge_7 0.07 0.01 7:1 700 100 3.51 no visible products yellow xtls; brwn Ge_8 0.08 0.01 8:1 800 100 3.55 powder Ge_9 0.09 0.01 9:1 900 100 3.61 yellow powder clumps Ge_10 0.10 0.01 10:1 1000 100 3.59 powder w/yellow xtls Ge_11 0.11 0.01 11:1 1100 100 3.39 yellow blades; blocks

* For each sample, mix appropriate amounts of GeO2, U-Nitrate, and H2O in a glass test tube. Measure/record pH. Transfer slurry/solution to Teflon liner. Heat at 220ºC for 7 days.

TABLE B.16 (CONTINUED)

Molarity Volume Sample U-Nitrate soln

# Ge U Ratio GeO2 soln (µL) (µL) pH Date/Notes Ge_12 0.12 0.01 12:1 1200 100 3.37 yellow fibers Ge_13 0.13 0.01 13:1 1300 100 3.44 yellow blades/blocks Ge_14 0.14 0.01 14:1 1400 100 3.47 yellow fibers Ge_15 0.15 0.01 15:1 1500 100 3.52 NR Ge_16 0.16 0.01 16:1 1600 100 3.55 NR Ge_17 0.17 0.01 17:1 1700 100 3.57 NR Ge_18 0.18 0.01 18:1 1800 100 3.57 NR Ge_19 0.19 0.01 19:1 1900 100 3.59 yellow fibers Ge_20 0.20 0.01 20:1 2000 100 3.67 orange clusters

178

TABLE B 17

SODIUM URANIUM GERMANATES*

Molarity Volume Sample 1 M NaOH # Ge U Ratio GeO2 soln (µL) U-Nitrate soln (µL) (µL) pH Date/Notes GeNa_1 0.01 0.01 1:1 100 100 10 NR NR

179 GeNa_2 0.02 0.01 2:1 200 100 10 NR NR

GeNa_3 0.03 0.01 3:1 300 100 10 11.62 NR

GeNa_4 0.04 0.01 4:1 400 100 10 11.28 NR GeNa_5 0.05 0.01 5:1 500 100 10 11.21 NR GeNa_6 0.06 0.01 6:1 600 100 10 11.31 powder GeNa_7 0.07 0.01 7:1 700 100 10 9.44 NR GeNa_8 0.08 0.01 8:1 800 100 10 11.32 NR GeNa_9 0.09 0.01 9:1 900 100 10 11.03 NR GeNa_10 0.10 0.01 10:1 1000 100 10 11.45 NR GeNa_11 0.11 0.01 11:1 1100 100 10 10.59 NR GeNa_12 0.12 0.01 12:1 1200 100 10 11.63 NR

* For each sample, mix appropriate amounts of GeO2, U-Nitrate, Base, and H2O in a glass test tube. Measure/record pH. Transfer slurry/solution to Teflon liner. Heat at 220ºC for 7 days.

TABLE B.17 (CONTINUED)

Molarity Volume Sample 1 M NaOH # Ge U Ratio GeO2 soln (µL) U-Nitrate soln (µL) (µL) pH Date/Notes GeNa_13 0.13 0.01 13:1 1300 100 10 9.42 NR GeNa_14 0.14 0.01 14:1 1400 100 10 9.4 NR GeNa_15 0.15 0.01 15:1 1500 100 10 11.43 NR GeNa_16 0.16 0.01 16:1 1600 100 10 8.46 ylw powder GeNa_17 0.17 0.01 17:1 1700 100 10 8.97 ylw powder GeNa_18 0.18 0.01 18:1 1800 100 10 7.98 ylw powder GeNa_19 0.19 0.01 19:1 1900 100 10 8.74 ylw powder GeNa_20 0.20 0.01 20:1 2000 100 10 8.07 ylw powder

180

TABLE B 18

POTASSIUM URANIUM GERMANATES*

Molarity Volume Sample 1 M KOH # Ge U Ratio GeO2 soln (µL) U-Nitrate soln (µL) (µL) pH Date/Notes GeK_1 0.01 0.01 1:1 100 100 10 11.53 dark ylw xtls GeK_2 0.02 0.01 2:1 200 100 10 10.5 brwn powder GeK_3 0.03 0.01 3:1 300 100 10 3.83 poorly xtline GeK_4 0.04 0.01 4:1 400 100 10 10.05 powder 181 GeK_5 0.05 0.01 5:1 500 100 10 7.05 red xtls

GeK_6 0.06 0.01 6:1 600 100 10 9.67 ylw xtls GeK_7 0.07 0.01 7:1 700 100 10 4.9 NR GeK_8 0.08 0.01 8:1 800 100 10 NR xtls w/o U GeK_9 0.09 0.01 9:1 900 100 10 5.82 xtls w/o U GeK_10 0.10 0.01 10:1 1000 100 10 8.83 NR GeK_11 0.11 0.01 11:1 1100 100 10 9.81 ylw fibers GeK_12 0.12 0.01 12:1 1200 100 10 8.98 ylw fibers GeK_13 0.13 0.01 13:1 1300 100 10 8.88 ylw fibers

* For each sample, mix appropriate amounts of GeO2, U-Nitrate, Base, and H2O in a glass test tube. Measure/record pH. Transfer slurry/solution to Teflon liner. Heat at 220ºC for 7 days.

TABLE B.18 (CONTINUED)

Molarity Volume Sample Ge U Ratio GeO2 soln U-Nitrate soln (µL) 1 M KOH pH Date/Notes # (µL) (µL) GeK_14 0.14 0.01 14:1 1400 100 10 9.11 NR GeK_15 0.15 0.01 15:1 1500 100 10 10.02 powder GeK_16 0.16 0.01 16:1 1600 100 10 9.53 powder GeK_17 0.17 0.01 17:1 1700 100 10 8.25 NR GeK_18 0.18 0.01 18:1 1800 100 10 8.33 ylw xtls GeK_19 0.19 0.01 19:1 1900 100 10 8.85 red xtls GeK_20 0.20 0.01 20:1 2000 100 10 8.84 xtls w/o U

182

TABLE B 19

RUBIDIUM URANIUM GERMANATES*

Molarity Volume Sample 1 M RbOH # Ge U Ratio GeO2 soln (µL) U-Nitrate soln (µL) (µL) pH Date/Notes GeRb_1 0.01 0.01 1:1 100 100 10 12.58 powder GeRb_2 0.02 0.01 2:1 200 100 10 11.74 orange xtls GeRb_3 0.03 0.01 3:1 300 100 10 11.22 No products GeRb_4 0.04 0.01 4:1 400 100 10 11.42 clear xtls 183 GeRb_5 0.05 0.01 5:1 500 100 10 10.81 clear xtls

GeRb_6 0.06 0.01 6:1 600 100 10 10.52 clear fibers GeRb_7 0.07 0.01 7:1 700 100 10 10.51 pale clumps GeRb_8 0.08 0.01 8:1 800 100 10 10.06 xtls w/o U GeRb_9 0.09 0.01 9:1 900 100 10 10.01 powder GeRb_10 0.10 0.01 10:1 1000 100 10 10.17 powder GeRb_11 0.11 0.01 11:1 1100 100 10 4.99 clear xtls GeRb_12 0.12 0.01 12:1 1200 100 10 10.02 blackened GeRb_13 0.13 0.01 13:1 1300 100 10 10.69 pale ylw xtls

* For each sample, mix appropriate amounts of GeO2, U-Nitrate, Base, and H2O in a glass test tube. Measure/record pH. Transfer slurry/solution to Teflon liner. Heat at 220ºC for 7 days.

TABLE B.19 (CONTINUED)

Molarity Volume Sample 1 M RbOH # Ge U Ratio GeO2 soln (µL) U-Nitrate soln (µL) (µL) pH Date/Notes GeRb_14 0.14 0.01 14:1 1400 100 10 10.52 geode-like GeRb_15 0.15 0.01 15:1 1500 100 10 11.09 powder GeRb_16 0.16 0.01 16:1 1600 100 10 10.32 powder GeRb_17 0.17 0.01 17:1 1700 100 10 10.13 powder GeRb_18 0.18 0.01 18:1 1800 100 10 9.24 powder GeRb_19 0.19 0.01 19:1 1900 100 10 9.1 sea-urchin GeRb_20 0.20 0.01 20:1 2000 100 10 8.74 powder

184

B.2 Rock-Forming Minerals

TABLE B 20

SYNTHESIS CONDITIONS FOR CALCITE BY PRECIPITATION/EVAPORTATION*

Trial mL H2O g CaCl2 mL H2O g Na2CO3 Add’n Method Precipitation Conditions Results 1 20 1.021 20 1.0641 constant drop desktop, 24 hours xtls (small) formed on glass slide

185 2 10 0.5545 10 0.53 constant drop desktop, 24 hours powder/xtls

3 10 0.5545 10 0.53 5 mL/hr drop desktop, 24 hours 4 10 0.5545 10 0.53 constant drop heated, not boiling; evap 5 10 0.5545 10 0.53 5 mL/hr drop heated, not boiling; evap 6 10 0.5545 10 0.53 constant drop heated til evap xtln powder; small ~5x5 micron 7 5 0.2773 5 0.265 constant drop desktop, 24 hours 8 5 0.2773 5 0.265 constant drop heated, not boiling; evap 9 5 0.2773 5 0.265 constant drop heated til evap xtln powder

* * Not successful for single crystal growth.

TABLE B 21

SYNTHESIS CONDITIONS FOR CERUSSITE BY PRECIPITATION/EVAPORATION*

Trial mL 0.1 M Pb(NO3)2 mL 0.5M Na2CO3 Conditions A 20 20 10 mL/min; 24 hours on desktop B 10 10 24 hours on desktop C 5 5 24 hours on desktop D 20 (0.5 M) 20 (1.0 M) 10 mL/min; 24 hours on desktop E 10 (0.5 M) 10 (1.0 M) 24 hours on desktop F 5 (0.5 M) 5 (1.0 M) 24 hours on desktop G 5 5 24 hours at 80ºC

186 H 5 (0.5 M) 5 (1.0 M) 24 hours at 80ºC

* Not successful for single crystal growth.

TABLE B 22

SYNTHESIS CONDITIONS FOR BARITE BY PRECIPITATION/EVAPORATION*

Trial mL x M BaCl2 mL x M Na2SO4 Conditions A 10 x 0.0033 10 x 0.0033 72 hours on desktop B 5 x 0.0033 5 x 0.0033 72 hours on desktop C 10 x 0.01 10 x 0.01 72 hours on desktop D 5 x 0.01 5 x 0.01 72 hours on desktop E 5 x 0.0033 5 x 0.0033 24 hours at 80ºC F 5 x 0.0033 5 x 0.0033 48 hours at 80ºC G 5 x 0.0033 5 x 0.0033 72 hours at 80ºC

187 H 5 x 0.01 5 x 0.01 24 hours at 80ºC

I 5 x 0.01 5 x 0.01 48 hours at 80ºC

J 5 x 0.01 5 x 0.01 72 hours at 80ºC K 10 x 1 10 x 1 72 hours on desktop

* Not successful for single crystal growth.

TABLE B 23

SYNTHESIS CONDITIONS FOR CELESTITE BY PRECIPITATION/EVAPORATION*

Trial mL x M SrCl2 mL x M Na2SO4 Conditons A 10 x 0.0033 10 x 0.0033 72 hours on desktop B 5 x 0.0033 5 x 0.0033 72 hours on desktop C 10 x 0.01 10 x 0.01 72 hours on desktop D 5 x 0.01 5 x 0.01 72 hours on desktop E 5 x 0.0033 5 x 0.0033 24 hours at 80ºC F 5 x 0.0033 5 x 0.0033 48 hours at 80ºC G 5 x 0.0033 5 x 0.0033 72 hours at 80ºC

188 H 5 x 0.01 5 x 0.01 24 hours at 80ºC

I 5 x 0.01 5 x 0.01 48 hours at 80ºC

J 5 x 0.01 5 x 0.01 72 hours at 80ºC K 10 x 1 10 x 1 72 hours on desktop

* Not successful for single crystal growth.

TABLE B 24

SYNTHESIS CONDITIONS FOR ANGLESITE BY PRECIPITATION/EVAPORATION*.

Trial mL x M PbCl2 mL x M Na2SO4 Conditons A 10 x 0.0033 10 x 0.0033 72 hours on desktop B 5 x 0.0033 5 x 0.0033 72 hours on desktop C 10 x 0.01 10 x 0.01 72 hours on desktop D 5 x 0.01 5 x 0.01 72 hours on desktop E 5 x 0.0033 5 x 0.0033 24 hours at 80ºC F 5 x 0.0033 5 x 0.0033 48 hours at 80ºC G 5 x 0.0033 5 x 0.0033 72 hours at 80ºC

189 H 5 x 0.01 5 x 0.01 24 hours at 80ºC

I 5 x 0.01 5 x 0.01 48 hours at 80ºC

J 5 x 0.01 5 x 0.01 72 hours at 80ºC K 10 x 1 10 x 1 72 hours on desktop

* Not successful for single crystal growth.

TABLE B 25

SYNTHESIS CONDITIONS FOR WITHERITE BY PRECIPITATION/EVAPORATION*

Trial mL x M BaCl2 mL x M NaHCO3 Conditions A 10 x 0.02 10 x 0.02 heat, slow add, 24 hours on desktop B 5 x 0.02 5 x 0.02 heat, slow add, 24 hours on desktop C 10 x 0.1 10 x 0.1 heat, slow add, 24 hours on desktop D 5 x 0.1 5 x 0.1 heat, slow add, 24 hours on desktop E 5 x 0.02 5 x 0.02 24 hours at 80ºC F 5 x 0.02 5 x 0.02 48 hours at 80ºC G 5 x 0.1 5 x 0.1 24 hours at 80ºC

190 H 5 x 0.1 5 x 0.1 48 hours at 80ºC

I 10 x 1 10 x 1 heat, slow add, 24 hours on desktop

* Not successful for single crystal growth.

TABLE B 26

SYNTHESIS CONDITIONS FOR STRONTIANITE BY PRECIPITATION/EVAPORATION*

Trial mL x M SrCl2 mL x M NaHCO3 Conditions A 10 x 0.02 10 x 0.02 heat, slow add, 24 hours on desktop B 5 x 0.02 5 x 0.02 heat, slow add, 24 hours on desktop C 10 x 0.1 10 x 0.1 heat, slow add, 24 hours on desktop D 5 x 0.1 5 x 0.1 heat, slow add, 24 hours on desktop E 5 x 0.02 5 x 0.02 24 hours at 80ºC F 5 x 0.02 5 x 0.02 48 hours at 80ºC G 5 x 0.1 5 x 0.1 24 hours at 80ºC

191 H 5 x 0.1 5 x 0.1 48 hours at 80ºC

I 10 x 1 10 x 1 heat, slow add, 24 hours on desktop

* Not successful for single crystal growth.

TABLE B 27

SYNTHESIS CONDITIONS FOR GYPSUM BY PRECIPITATION/EVAPORATION*

Trial mL x M CaCl2 mL x M Na2SO4 Conditions A 10 x 0.6 10 x 0.6 Heat, 2 hours, filter B 5 x 0.5 5 x 0.5 Heat, 2 hours, filter C 10 x 1 10 x 1 Heat, 2 hours, filter D 5 x 1 5 x 1 Heat, 2 hours, filter E 5 x 0.6 5 x 0.6 2 hours at 80ºC

F 5 x 1 5 x 1 2 hours at 80ºC 192

* Not successful for single crystal growth.

TABLE B 28

SYNTHESIS CONDITIONS FOR CALCITE BY PRECIPITATION/EVAPORATION*

Trial mL x M CaCl2 mL x M Na2CO3 mL x M NaCl Conditions A 10 x 1 10 x 1 10 x 0.5 24 hours desktop B 5 x 1 5 x 1 5 x 0.5 24 hours desktop C 10 x 1 10 x 1 - 24 hours desktop D 5 x 1 5 x 1 - 24 hours desktop E 5 x 1 5 x 1 - 3 hours at 80ºC F 5 x 1 5 x 1 - 24 hours at 80ºC G 5 x 1 5 x 1 - 3 hours at 150ºC

193 H 5 x 1 5 x 1 - 24 hours at 150ºC

* Not successful for single crystal growth.

TABLE B 29

ORIGINAL SYNTHESIS FOR CALCITE AND GYPSUM IN TETRAMETHOXYSILANE GEL*

mL (CH3O)4Si + mL H2O mL x M CaCl2 mL x M (NH4)2CO3 mL x M Na2SO4 mL x M Pb(NO3)2 SrCl2 TMOS Gel 9 x 81 - - - - - Calcite - 5 x 0.16 5 x 0.16 - - - Gypsum - 5 x 0.6 - 5 x 0.6 - - Cerussite - - - 5 x 0.5 (Na2CO3) 5 x 0.1 - - - - 5 X 0.1 - 5 X 0.1

194

* Allow (CH3O)4Si and water to mix for 15 minutes with stir bar. Pipette gel solution into glass U-shaped tube and allow to set-up for 12 hours. Once gel is set, layer Ca or Sr and CO3, NO3 or SO4 solutions in opposite arms of tube. Neptunium trials were carried out for calcite using this method with concentrations of Np(V) at 400 and 800 ppm relative to Ca.

TABLE B 30

A SELECTION OF SYNTHESIS CARRIED OUT IN STRAIGHT, OPEN-ENDED GLASS TUBES*

Sample mL TMOS g CaCl2 mL H2O pH mL of 0.20 M (NH4)2CO3 1 0.3 0.10 5.7 5.07 2 2 0.3 0.32 5.7 5.17 2 3 0.3 0.63 5.7 5.17 2 4 0.6 0.096 5.4 5.25 2 5 0.6 0.30 5.4 5.23 2 6 0.6 0.60 5.4 5.20 2 7 0.9 0.091 5.1 5.18 2

195 8 0.9 0.28 5.1 5.16 2

9 0.9 0.57 5.1 5.18 2

* TMOS is mixed with CaCl2 and H2O to form gel at bottom of tube. Bottom of tube should be covered with Parafilm until gel sets. Once gel is set, (NH4)2CO3 solution may be overlain. Density of gel and concentration of Ca and CO3 solutions were varied with crystals appearing at the solution-gel interface, as well as, within the gel.

B.3 Maya Reimi’s Summer Notebook 2011

Includes synthesis of calcite in gel and in solution via Fernelius and Detling method, synthesis of gypsum and strontianite via Fernelius and Detling method, and attempt to synthesize dolomite via Fernelius and Detling method.

Date: Preparing the Calcite in Gel experiment 06/06/2011

Make Solutions of CaCl2, (NH4)2CO3 and TMOS 0.5782 g of CaCl2 /10mL H2O .4797g of (NH4)2CO3/10ml H2O

196

Made 3 tubes, mixed .9mL of TMOS and 5.1mL CaCl2. Placed 2ml of solution in a parafilmed open ended tube.

Date: Creating Solutions for Fernelius Experiment 06/21/2011

Prepare two beakers of gypsum, two beaker of calcite in ultrapure water and one beaker of calcite in acid water. 15ml of CaCl (9 g in 15m of H2O) 15 ml of (NH4)2CO3 (4.5 g in 15ml of H2O) .33 g of Na2SO4 in 1.5ml of H2O

N1 (supersaturated) N2 G1

G2 A1 pH= 2.46 A2 ph= 2.46 Filled the water of a 100 ml Beaker up until there was about 2 centimeters of water above the little vials.

Date: Results from the first Fernelius Experiment 06/22/2011

N1 and N2 failed (powdery precipitation and cloudy water). Created N3 and N4 with the same solutions.

Date: More experiments 06/23/2011

197

N3 and N4 also failed.

New CaCl2 and (NH4)2CO3 solutions CaCl2. 15ml of H2O and 4.327 grams of CaCl2, anhydrous 96%

(NH4)2CO3, 15ml H2O and 6.8102 g of (NH4)2CO3

Date: 06/27/2011

Create another gypsum with CaCl2 from 06/21 (not sure about the source for the sulfate).

Diluted the solution of CaCl2 from 06/21 with 7ml of H2O. Created a Normal Calcite and Acidic Calcite and another gypsum with the diluted solution.

NOTE: No crystallization in the gypsum.

Date: Gypsum and Uranium 06/02/2011

The concentrate gypsum as well as the calcite in acid water were relatively successful (there was too much material in the concentrated gypsum).

Low Concentration Gypsum

CaCl2: 1.9g/15ml H2O Na2SO4: 1.1 g/15ml H2O

198 800ppm U

1.5 ml of each solution, 75ml of H2O and 7µl of U.

400ppm U, 1.5 ml of each solution, 75ml of H2O and 3µl of U.

Note: did not work, no crystallization in over a month.

High Concentration Gypsum CaCl2: 13.23g/15ml Na2SO4: 1.1g/18ml

800ppm 1.5 ml of each solution, 75ml of H2O and 45µl of U.

400ppm U, 1.5 ml of each solution, 75ml of H2O and 22µl of U. Note: The high concentration experiments had small cluster of crystallized gypsum, however there was a powdery green/yellow precipitate in the (NH4)2CO3 vial, it seemed that the experiments crash with the Uranium possibly forming a chlorine compound.

Date: Calcite and Uranium 06/29/2011

Saturated CaCl2 Grams of H2O Grams of CaCl2 96% anhydrous 15.0439 2.7494 (added slowly)

199 Saturated (NH4)2CO3

Grams of H2O Grams of (NH4)2CO3 15.1612 6.054 (added slowly)

Using U stock solution 100mmol

Cal_U_800ppm_1 Cal_U_800ppm_2 Cal_U_400ppm_1 Cal_U_400ppm_2 75.0405 g H2O 75.1055 g H2O 75.1133 g H2O 75.0464 g H2O pH= 3.41 pH= 3.30 pH= 3.54 pH= 3.63 U= 9ul U= 9ul U= 5ul U= 5ul 1.5 ml of each 1.5 ml of each 1.5 ml of each 1.5 ml of each solution solution solution solution

Date: SrCO3 07/01/2011

SrCl2 saturated solution 15ml of H20 8.5073 g of SrCl2 Hexahydrate

Date: General observations 07/07/2011

200 1. CaCO3 with 800 and 400ppm U formed crystals about 20um, too small to determine weather ot not they are CaCO3 (at

first sight). We think that the lack of well-formed crystals might be due to the pH level of the experiments. 2. CaCO3 in acid water with no uranium formed crystals larger than 100um long, and not much powder. The water had a pH of 2.09, this will become the target acidity. 3. SrCO3 (running for a week), formed a web of dendritic crystals, but there was too much happening in the system and too much powder. The experiment will be repeated with lower concentration of SrCO3 4. The High concentration gypsum with 800 and 400 ppm U precipitated gypsum in the Na2SO4 vials while it precipitated a green powdery substance in the CaCl2 vial.

Set up a new SrCO3 experiment.

Diluted the SrCl2 sol from 07/01/11, 10 ml of solution and 5ml of H20.

New Solutions of Ca and NH4 for new calcite with U

Saturated CaCl2 Grams of H2O Grams of CaCl2 96% anhydrous 15 2.7783 (added slowly)

Saturated (NH4)2CO3 Grams of H2O Grams of (NH4)2CO3 15 6.0065 (added slowly)

Date: New Calcite with U 07/08/2011

201 New Calcite with U using solutions from 07/07

Cal_U_800ppm_3 Cal_U_400ppm_1 Cal_U_400ppm_2 60.0079 g H2O 60.1630 g H2O 60.0940 g H2O HCl: 1040 ul HCl: 450 ul HCl: 350 ul pH= 2.19 pH= 2.18 pH= 2.19 U= 9ul U= 5ul U= 5ul 1.5 ml of each solution 1.5 ml of each solution 1.5 ml of each solution

Create a new SrCO3 with new solutions

Date: Dolomite and more Gypsum 07/12/2011

Dolomite_1:

CaCl2, MgNO3, (NH4)2CO3 (from 7/7)

Saturated CaCl2 for gypsum Grams of H2O Grams of CaCl2 15.0755 4.6141 (added slowly)

Saturated CaCl2 Grams of H2O Grams of CaNO3 15.0171 6.1595 (added slowly)

Saturated (NH4)2CO3 Grams of H2O Grams of (NH4)2CO3 202 15 6.0065 (added slowly)

Date: Dolomite, cont. 06/13/2011

Dolomite_1 Dolomite_2 1.5 ml of CaCl from 07/07 1.5 ml of CaNO3 from 07/12 1.5ml of NH4CO3 from 07/07 1.5ml of NH4CO3 from 07/07 D1 water (1.1877 MgNO3/60ml H2O). D2 water (1.3383 MgNO3/60ml H2O). Initial pH: 5.18 Initial pH: 5.16 Final pH: 2.11 Final pH: 2.06 HCl: 400 ul HCl: 400 ul

MgNO3 in water (outside solution) D1 Grams of H2O Grams of MgNO3 60.1314 1.1877

D2 MgNO3 in water Grams of H2O Grams of MgNO3 203 60.0607 1.3383

Date: Ph in Calcite water 07/14/2011

Saturated CaCl2 for Calcite Grams of H2O Grams of CaCl2 15.0088 2.8088 (added slowly)

Saturated (NH4)2CO3 Grams of H2O Grams of (NH4)2CO3 15.0016 5.9387 (added slowly)

Beaker (exp) Water (g) Final .1 M HCl Added .424 M (NH4)2CO3 pH (ul) (ul) C1 60.1384 1.15 18600 ------204 C2 60.0145 2.03 2000 ------

C3 60.0371 3.08 150 ------C4 60.2089 4.01 20 ------C5 60.1484 4.97 2 ------C6 60.6879 6.04 ------5

Date: Neptunium Experiments 07/18/2011 Create sol of CaCl2 and (NH4)2CO3

Saturated CaCl2 for Calcite ULTRAPUTE 99.999

Grams of H2O Grams of CaCl2 18.0103 3.3250 (added slowly)

Saturated (NH4)2CO3 ULTRAPURE 99.99

Grams of H2O Grams of (NH4)2CO3 15.0229 3.6375 (added slowly)

10 mM U, 17 and 42 ul for 400 and 1000ppm

Exp Water .1 M pH bef pH pH day Day 3 Day 5 Day 7 HCl after 1 205 Np_400_1_C 60.2194 550 3.4 2.18 7.02 7.01 7.35

Np_400_2_C 60.0415 550 3.24 2.17 2.36 6.93 6.95 7.05 Np_1000_1_C 60.0211 450 2.83 2.19 2.42 7.01 6.85 7.40 Np_1000_2_C 60.0428 450 2.85 2.20 2.49 7.23 6.92 7.25 U_400_1_C 60.1218 150 4.66 2.15 2.58 6.62 6.87 7.37 U_400_2_C 60.1093 150 4.12 2.17 2.94 6.67 7.10 7.00 U_1000_1_C 60.0123 100 3.80 2.19 2.93 6.72 7.12 7.13 U_1000_2_C 60.0842 100 3.86 2.15 2.54 6.75 6.79 7.39 Blank 59.9501 450 4.71 2.21 2.11 7.08 7.30 7.35 (7/25)

Date: Dolomite, again 07/21/2011

1. Create new dolomite (1 w/Mg in the water from day 1, another one w/o Mg and add the Mg after the calcite forms).

2. Create 6 different concentration of Gypsum changing the CaCl2 concentration keeping Na2SO4

Saturated CaCl sol

Grams of H2O Grams of CaCl2 15.0860 12.5739 (added slowly)

Saturated Na2SO4

Grams of H2O Grams of Na2SO4

18.0343 6.2864 206

Different Concentrations

Exp. Concentration of Dissolution Result sol. (12.5g/15) CaCl2 1 100 ------Too many xls, xls everywhere 2 85 2.55ml of sol + .45ml H20 Great amount of xls 3 60 1.8 ml of sol + 1.2 ml H2O xls 4 45 1.35 ml of sol + 1.65 ml xls H2O 5 30 .9 ml of sol + 2.1 ml H2O Few xls 6 Just a saturated ------Good amount of xls leftover

207

Best Concentration, 85%

Date: Last pH of Calcite Exp 07/22/2011

Exp pH day 7 C1 1.20 C2 6.97 C3 7.86 C4 7.97 C5 7.95 C6 7.95

Date: Create a new Gyp w/ Uranium 07/25/2011

Sol : 1.5 ml of 85 CaCl2 208

1,5 ml of Na2SO4 7/21

Gyp_U_400ppm_1 Gyp_U_1000ppm_1 59.9718 g H2O 60.9885 g H2O pH= 4.54 pH= 5.07 (NH4)OH = 30 ul .42 M (NH4)OH = 70 U= 6ul ul 1.5 ml of each U= 16ul solution 1.5 ml of each solution

Date: More U Gypm

07/26/2011

Gyp_U_800ppm_2 Gyp_U_1000ppm_2 60 g H2O 60 g H2O U= 6ul U= 16ul 1.5 ml of each 1.5 ml of each solution solution

Saturated (NH4)2CO3 for SrCO3 Grams of H2O Grams of (NH4)2CO3 15.0343 4.0124 (added slowly)

209 Use dilutes SrCO3 from 07/07 and acid water pH= 2.23

Date: SrCO3 and Uranium 07/29/2011

Solution of 5.671 g of SrCl2 in 15ml of H2O Exp 100 Water .1 M pH bef pH mM U HCl after 400 S1 4 60.0149 950 3.83 2.08 400 S2 4 59.9851 ---- 3.41 --- 1000 S3 9 60.1691 500 3.58 2.18 1000 S4 9 60.0033 --- 3.45 ---

Date: Solution for Gypsum Np 08/03/2011

Saturated Na2SO4 ultrapute

Grams of H2O Grams of Na2SO4 210 20ml 6.6703 (added slowly)

Date: More Ultrapure solutions 08/08/2011

Saturated (NH4)2CO3 for SrCO3 ULTRAPURE Grams of H2O Grams of (NH4)2CO3 20 5.3621 (added slowly)

Saturated SrCl2 for SrCO3 ULTRAPURE Grams of H2O Grams of SrCl2

20 7.5585 (added slowly)

211

APPENDIX C:

URANIUM DATABASE PARAMETERS

212

TABLE C 1

URANIUM DATABASE PARAMETERS

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Walpurgi Bi4O4[(UO2)(A 10.4 110.8 natura Infinite As te sO4)2](H2O)2 7.135 26 5.494 101.47 2 88.2 Mereiter 1982 l Chains Orthowa Bi4O4[(UO2)(A 13.3 20.68 natura Infinite 213 As lpurgite sO4)2](H2O)2 5.492 24 5 90 90 90 Krause 1995 l Chains

UO2(H2AsO4)2 13.16 8.86 124.4 soluti Infinite

As (H2O) 4 2 9.05 90 1 90 Gesing 2000 on RT Chains Hallimon Pb2[(UO2)(AsO 7.115 10.4 6.857 101.17 95.71 soluti 151- Infinite As dite 4)2](H2O)n 3 78 1 8 1 86.651 Locock 2005 on 300 Chains Abernat K[(UO2)(AsO4)] 7.17 18.12 natura As hyite (H2O)3 7.176 6 6 90 90 90 Ross 1964 l Sheets - V Zeunerit Cu[(UO2)(AsO4 7.179 7.17 20.85 soluti As e )]2(H2O)12 7 97 7 90 90 90 Locock 2003 on RT Sheets - V Metazeu Cu[(UO2)(AsO4 7.109 7.10 17.41 soluti 151- As nerite )]2(H2O)8 4 94 6 90 90 90 Locock 2003 on 300 Sheets - V NH4[(UO2)(AsO 7.18 18.19 soluti As 4)](H2O)3 7.189 9 1 90 90 90 Ross 1964 on RT Sheets - V KH3O[(UO2)(As 7.17 18.04 soluti As O4)]2(H2O)6 7.171 1 8 90 90 90 Ross 1964 on RT Sheets - V [(UO2)D(AsO4)] 7.161 7.16 17.63 soluti As (D2O)4 5 15 899 90 90 90 Fitch 1983 on RT Sheets - V

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Li[(UO2)(AsO4) 7.096 7.09 9.190 soluti As ](D2O)4 9 69 3 90 90 90 Fitch 1982 on RT Sheets - V Mg[(UO2)(AsO4 18.20 7.06 natura As )]2(H2O)4 7 2 6.661 90 99.65 90 Bachet 1991 l Sheets - TSP Pb2[(UO2)3O2( 31.06 17.3 96.49 natura Sheets - As Hugelite AsO4)2](H2O)5 6 03 7.043 90 2 90 Locock 2003 l TSPH (UO2)[(UO2)(A 11.23 7.15 21.94 104.5 soluti 151- Infinite As sO4)]2(H2O)4 8 2 1 90 76 90 Locock 2003 on 300 Frameworks (UO2)[(UO2)(A 20.13 11.6 soluti 151- Infinite As sO4)]2(H2O)5 3 95 7.154 90 90 90 Locock 2003 on 300 Frameworks Cs2(UO2)[(UO2 15.15 14.0 13.43 soluti 151- Infinite As )(AsO4)]4(H2O) 7 79 9 90 90 90 Locock 2003 on 300 Frameworks Rb2(UO2)[(UO2 )(AsO4)]4(H2O) 13.46 15.8 14.00 92.31 soluti 151- Infinite

214 As 4.5 19 463 68 90 1 90 Locock 2003 on 300 Frameworks Mn[(UO2)(AsO4 7.135 7.14 11.36 81.63 soluti As )2](H2O)12 9 39 16 81.592 9 88.918 Locock 2004 on RT Sheets Co[(UO2)(AsO4 7.155 7.15 11.29 soluti As )2](H2O)12 2 86 12 81.487 81.41 88.891 Locock 2004 on 0-20 Sheets Mg[(UO2)(AsO4 7.159 7.16 11.31 81.17 soluti As )2](H2O)12 4 1 46 81.391 7 88.884 Locock 2004 on RT Sheets Ni[(UO2)(AsO4) 7.152 7.15 11.25 81.35 soluti As 2](H2O)12 3 83 64 81.549 6 88.916 Locock 2004 on RT Sheets Co[(UO2)(AsO4 7.195 9.77 13.23 84.05 soluti 151- As )2](H2O)8 5 15 19 75.525 2 81.661 Locock 2004 on 300 Sheets Fe[(UO2)(AsO4 7.207 9.82 13.27 75.370 84.02 soluti 151- As )2](H2O)8 2 42 08 1 4 81.839 Locock 2004 on 300 Sheets Mn[(UO2)(AsO4 7.224 9.91 13.33 84.13 soluti 151- As )2](H2O)8 4 7 7 75.012 6 81.995 Locock 2004 on 300 Sheets Mg[(UO2)(AsO4 7.132 20.0 7.156 90.58 soluti As )2](H2O)10 8 85 9 90 5 90 Locock 2004 on RT Sheets

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Rb[(UO2)(AsO4 7.190 7.19 17.64 soluti As )](H2O)3 4 04 3 90 90 90 Locock 2004 on RT Sheets Ag[(UO2)(AsO4 7.090 7.09 17.04 soluti 151- As )](H2O)3 1 01 53 90 90 90 Locock 2004 on 300 Sheets Tl[(UO2)(AsO4) 7.190 7.19 soluti 151- As ](H2O)3 5 05 17.97 90 90 90 Locock 2004 on 300 Sheets Cs(H3O)[(UO2)( 14.26 7.14 17.22 soluti As AsO4)]2(H2O)5 14 28 1 90 91.11 90 Locock 2004 on RT Sheets K[(UO2)(AsO4)] 7.166 7.16 17.86 soluti 151- As (H2O)3 9 69 7 90 90 90 Locock 2004 on 3000 Sheets Na[(UO2)(AsO4 7.150 7.15 17.32 soluti As )](H2O)3 4 04 5 90 90 90 Locock 2004 on RT Sheets Sr[(UO2)(AsO4) 7.10 18.90 Pushcharov soluti Infinite As ]2(H2O)8 7.154 1 1 90 92.67 90 skii 2005 on 31-150 Frameworks

215 Sr[(UO2)(AsO4) 14.37 20.9 7.170 soluti As ]2(H2O)11 78 611 3 90 90 90 Locock 2005 on RT Sheets K(AsUO6)(H2O) 17.74 soluti 151- As 3 7.16 7.16 62 90 90 90 Alekseev 2005 on 300 Sheets K2[(UO2)As2O7 12.60 13.2 solid 501- As ] 1 42 5.621 90 90 90 Alekseev 2007 state 1000 Sheets (UO2)2(AsO4)( uramarsi PO4)(NH4)(H3 7.16 Rastsvetae natura As te O)(H2O)6 7.173 7 9.3 90.13 90.09 89.96 va 2008 l Sheets [((Mg0.81Fe0.1 9)(H2O)6)(H2O )4][(UO2)((P0.6 19.8 6.969 90.80 natura As 7As0.33)O4)]2 6.952 65 5 90 6 90 Yakubovich 2008 l Sheets a- Li[(UO2)(AsO4) 10.1 102.5 solid 501- Infinite As ] 5.129 05 11.08 107.7 3 104.74 Alekseev 2008 state 1000 Frameworks

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe B- Li[(UO2)(AsO4) 5.30 10.10 solid 501- Infinite As ] 5.051 3 1 90.31 97.49 105.08 Alekseev 2008 state 1000 Frameworks Ba4[(UO2)7(UO 15.53 7.04 14.09 solid Infinite As 4)(AsO4)2O7] 5 2 4 90 90 90 Wu 2009 state 1000+ Frameworks Li3[(UO2)7(AsO 7.21 14.65 solid 501- Infinite As 4)5O) 7.216 6 4 90 90 90 Alekseev 2009 state 1000 Frameworks Li[(UO2)4(AsO4 33.77 solid 501- Infinite As )3] 7.16 7.16 5 90 90 90 Alekseev 2009 state 1000 Frameworks Li5[(UO2)13(As 13.9 31.92 88.69 solid 501- Infinite As O4)9(As2O7)] 7.141 59 5 82.85 1 79.774 Alekseev 2009 state 1000 Frameworks (Hg5O2(Oh)4)[( 6.822 6.87 9.595 109.45 104.8 soluti 151- Infinite As UO2)(AsO4)2] 9 95 9 6 34 93.867 Yu 2009 on 300 Frameworks Rb[(UO2)2(As3 10.55 11.0 11.46 solid 501- Infinite

216 As O10)] 8 37 4 90 90 90 Alekseev 2009 state 1000 Frameworks Ag6[(UO2)2(As 27.5 105.0 solid 501- As 2O7)(As4O13)] 8.963 76 9.207 90 4 90 Alekseev 2009 state 1000 Sheets Nielsboh K(UO2)3(AsO4) 11.4 natura Infinite As rite (OH)4(H2O) 8.193 3 13.5 90 90 90 Walenta 2009 l Frameworks Ag6[(UO2)2(As 11.21 11.7 14.14 solid 501- As O4)2(As2O7)] 8 29 6 108.69 91.94 97.63 Alekseev 2009 state 1000 Sheets Na6[(UO2)2(As 10.99 11.6 14.05 solid 501- As O4)2(As2O7)] 6 33 7 108.63 91.27 97.4 Alekseev 2009 state 1000 Sheets (NH4)13[(NH4) (UO2)2(As2W1 12.48 20.2 17.57 101.4 Khoshnava soluti As 8O68)](H2O)17 8 84 9 90 3 90 zi 2006 on 0-20 Sheets Mg ((U O2) (As O3)0.7 (As O4)0.3)2 (H2 18.19 7.07 No No As O)7 39 1 6.67 90 99.7 90 1994 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe (N H4)17 ((U O2)3 (H2 O)4 (As3 W26 O94)) 40.17 18.2 18.08 No No As (H2 O)43 47 584 17 90 90 90 2002 data data No data K6[(UO2)B16O 24(OH)8](H2O) 12.02 26.4 12.54 soluti Finite B 12 4 5 3 90 94.74 90 Behm 1985 on RT Clusters Na[(UO2)(BO3) 10.71 solid B ] 2 5.78 6.862 90 90 90 Gasperin 1988 state 1000+ Sheets - TSP 10.5 105.0 solid B Li[(UO2)(BO3)] 5.767 74 6.835 90 4 90 Gasperin 1990 state 1000+ Sheets - TSP [Mg(UO2)(B2O 7.31 solid B 5)] 9.747 5 7.911 90 90 90 Gasperin 1987 state 1000+ Sheets - TSP [Ca(UO2)2(BO3 16.51 8.16 solid Sheets -

217 B )2] 2 9 6.582 90 96.97 90 Gasperin 1987 state 1000+ TSPH [(UO2)(B2O3)O 12.50 4.18 10.45 122.1 solid B ] 4 3 3 90 8 90 Gasperin 1987 state 1000+ Sheets - H 10.46 4.18 5.625 109.7 soluti 151- B (UO2)(B2O4) 07 63 1 90 69 90 Wang 2010 on 300 Sheets (UO2)2(B13O2 0(OH)3)(H2O)1. 6.473 10.7 19.66 soluti 151- B 25 2 981 53 85.711 82.66 89.287 Wang 2010 on 300 Sheets Na(UO2)(B6O1 6.390 11.1 15.98 92.77 soluti 151- B 9(OH))(H2O)2 5 39 7 90 7 90 Wang 2010 on 300 Sheets U O2 B12 H12 14.51 9.64 117.7 No No B (H2 O)11 3 1 9.705 90 6 90 1982 data data No data No No B Ni7 B4 U O16 5.861 20.2 4.501 90 90 90 1989 data data No data 8.13 solid 501- Ba Ba[(UO2)O2] 5.744 6 8.237 90 90 90 Reis 1976 state 1000 Sheets - V Ba[(UO2)3O3(O 12.29 7.22 6.955 90.40 natura Ba Protasite H)2](H2O)3 49 06 8 90 1 90 Pagoaga 1987 l Sheets - TP

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Ba[(UO2)3O3(O 12.07 30.1 7.145 natura Ba Billietite H)3]2(H2O)4 2 67 5 90 90 90 Pagoaga 1987 l Sheets - TP 8.37 No No Infinite Ba Ba2MgUO6 8.379 9 8.379 90 90 90 Padel 1972 data data Frameworks Ba[(UO2)6O4(O 12.09 30.2 7.156 natura Ba H)6](H2O)8 41 11 3 90 90 90 Finch 2006 l Sheets 6.161 6.11 8.697 90.10 solid Infinite Ba Ba2CaUO6 5 88 5 90 05 90 Fu 2008 state 1000+ Frameworks Uranosp 7.81 soluti 151- Bi haerite [Bi(UO2)O2OH] 7.559 1 7.693 90 92.88 90 Hughes 2003 on 300 Sheets - TSP Bi2[(UO2)O2]O 4.00 solid 501- Bi 2 6.872 9 9.69 90 90.16 90 Koster 1975 state 1000 Sheets - H 8.63 solid Infinite Bi K9BiU6O24 8.631 1 8.631 90 90 90 Gasperin 1991 state 1000+ Frameworks

218 Na14 (Bi U W9 O35 (H2 O)2)2 33.84 21.1 13.24 No No Bi (H2 O)33 54 484 03 90 90 90 2007 data data No data Br2(UO2)(H2O) 6.056 10.5 10.36 99.61 soluti Br 2 8 117 23 90 6 90 Crawford 2004 on 31-150 Sheets Br2(UO2)(H2O) 9.737 6.54 12.81 94.10 soluti Br 3 6 71 78 90 4 90 Crawford 2004 on 31-150 Sheets (N H4)2 U O2 6.88 No No Br Br4 (H2 O)2 6.885 7 7.737 94.44 98.78 116.79 1987 data data No data Ca2[(UO2)(CO3 16.69 17.5 13.69 natura Finite C Liebigite )3](H2O)11 9 57 7 90 90 90 Mereiter 1982 l Clusters NaCa3[(UO2)(C Schrocki O3)3](SO4)F(H 9.63 14.39 natura Finite C ngerite 2O)10 9.634 5 1 91.41 92.33 120.26 Mereiter 1986 l Clusters Mg2[(UO2)(CO3 15.2 soluti Finite C Bayleyite )3](H2O)18 26.56 56 6.505 90 92.9 90 Mayer 1986 on RT Clusters Swartzit CaMg[(UO2)(CO 14.6 soluti Finite C e 3)3](H2O)12 11.08 34 6.439 90 99.43 90 Mereiter 1986 on RT Clusters

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Anderso Na2Ca[(UO2)(C 17.90 17.9 23.75 natura Finite C nite O3)3](H2O)5 4 04 3 90 90 120 Mereiter 1986 l Clusters Grimselit K3Na[(UO2)(CO 9.30 soluti Finite C e 3)3](H2O) 9.302 2 8.26 90 90 120 Li 2001 on RT Clusters Na4[(UO2)(CO3 9.29 12.89 soluti Finite C Cejkaite )3] 9.291 2 5 90.73 90.82 120 Ondrus 2003 on RT Clusters Rb6Na2[(UO2)( 9.431 9.43 8.359 soluti Finite C CO3)3]2(H2O) 6 16 5 90 90 120 Kubatko 2003 on RT Clusters Cs4[(UO2)(CO3 18.72 9.64 11.29 soluti Finite C )3](H2O)6 3 7 7 90 96.84 90 Mereiter 1988 on RT Clusters Sr2[(UO2)(CO3) 11.37 11.4 25.65 soluti Finite C 3](H2O)8 9 46 3 90 93.4 90 Mereiter 1986 on RT Clusters (NH4)4[(UO2)( 10.67 9.37 No No Finite C CO3)3] 9 3 12.85 90 96.43 90 Serezhkin 1983 data data Clusters

219 Na4[(UO2)(CO3 9.341 9.34 12.82 soluti 151- Finite C )3] 7 17 4 90 90 120 Li 2001 on 300 Clusters Ca5[(UO2)(CO3 )3]2(NO3)2(H2 6.572 16.5 15.19 90.49 soluti Finite C O)10 9 17 5 90 4 90 Li 2002 on RT Clusters Ca6[(UO2)(CO3 16.74 16.7 soluti Finite C )3]2Cl4(H2O)19 4 44 8.136 90 90 90 Li 2002 on RT Clusters Ca12[(UO2)(CO 3)3]4Cl8(H2O)4 27.48 27.4 27.48 soluti Finite C 7 9 89 9 90 90 90 Li 2002 on RT Clusters Cs4[(UO2)(CO3 11.51 9.60 12.91 93.76 Krivoviche soluti Finite C )3] 31 37 77 90 7 90 v 2004 on RT Clusters K2Ca3[(UO2)(C 17.01 18.0 18.39 soluti Finite C O3)3]2(H2O)6 5 48 4 90 90 90 Kubatko 2004 on RT Clusters CaU5+(UO2)2(C O3)O4(OH)(H2 11.27 7.10 20.80 natura C Wyartite O)7 06 55 7 90 90 90 Burns 1999 l Sheets - TSP

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Fontanit Ca[(UO2)3(CO3 17.2 15.37 90.06 natura Sheets - C e )2O2](H2O)6 6.968 76 7 90 4 90 Hughes 2003 l TSPH [Cu2(UO2)3(CO Roubault 3)2O2(OH)2](H 6.92 natura Sheets - C ite 2O)4 7.767 4 7.85 92.16 90.89 93.48 Ginderow 1985 l TSPH Rutherfo 9.27 natura C rdine [UO2CO3] 4.84 3 4.298 90 90 90 Finch 1999 l Sheets - H [M3+(H2O)25( UO2)16O8(OH) Bijvoetit 8(CO3)16](H2O 21.23 12.9 44.91 natura C e )14 4 58 1 90 90 90 Li 2000 l Sheets - Misc Ca[U5+(UO2)2( CO3)0.7O4(OH) 11.26 7.08 16.83 natura C wyartite 1.6](H2O)1.63 1 7 59 90 90 90 Hawthorne 2006 l Sheets

220 SrMg[UO2(CO3) 11.21 14.7 soluti C 3](H2O)12 6 39 6.484 90 99.48 90 Alekseev 1986 on RT Sheets 10.24 9.20 12.22 No No C K4 U O2 (C O3)3 7 2 6 90 95.11 90 Anderson 1980 data data No data Tl4 ((U O2) (C 10.68 9.30 12.72 No No C O3)3) 4 9 6 90 94.95 90 1986 data data No data Na0.79 Sr1.40 Mg0.17 (U O2 (C O3)3) (H2 20.2 No No C O)4.66 20.29 9 20.29 90 90 90 1988 data data No data Ca3 Na1.5 (H3 O)0.5 (U O2 (C 16.8 18.43 No No C O3)3)2 (H2 O)8 18.15 66 6 90 90 90 1994 data data No data K4 (U (C O3)2 O2 (O2)) (H2 6.907 9.23 21.80 No No C O)2.5 7 32 9 90 91.31 90 2005 data data No data K4 (U O2 (O2) 9.21 18.05 91.51 No No C (C O3)2) (H2 O) 6.967 58 2 90 1 90 2008 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe van 5.729 5.96 8.299 Duivenbod solid Isolated Ca Ca3[UO6] 2 2 1 90 90.56 90 en 1986 state 1000+ Polyhedra 7.913 5.44 11.44 108.8 No No Infinite Ca Ca2[(UO2)O3] 7 09 82 90 03 90 Loopstra 1969 data data Chains Becquer Ca[(UO2)3O2(O 13.85 12.3 14.92 soluti 151- Ca elite H)3]2(H2O)8 27 929 97 90 90 90 Burns 2002 on 300 Sheets - TP Ca[(UO2)4O3(O 8.055 8.42 10.95 87.92 soluti 151- Ca H)4](H2O)2 6 12 8 78.878 2 72.277 Glatz 2002 on 300 Sheets - TSP 6.268 6.26 6.268 No No Ca Ca[(UO2)O2] 3 83 3 36.04 36.04 36.04 Loopstra 1969 data data Sheets - H 6.23 solid 501- Cd α-Cd[(UO2)O2] 6.233 3 6.233 36.12 36.12 36.12 Yamashita 1981 state 1000 Sheets - H 6.84 solid 501- Infinite

221 Cd β-Cd(UO2)O2 7.023 9 3.514 90 90 90 Yamashita 1981 state 1000 Frameworks 12.00 7.69 solid 501- Isolated Cl Cs2[(UO2)Cl4] 5 7 5.85 90 100 90 Tutov 1991 state 1000 Polyhedra [(UO2)Cl2(H2O) 12.73 10.4 No No Isolated Cl 3] 8 95 5.547 90 90 90 Debets 1968 data data Polyhedra [(UO2)(H2O)5]( 5.293 16.4 14.80 99.84 soluti Isolated Cl ClO4)2 5 543 18 90 71 90 Fischer 2003 on RT Polyhedra [(UO2)(H2O)5]( 14.49 9.21 10.67 soluti Isolated Cl ClO4)2dot2H2O 5 6 5 90 90 90 Fischer 2003 on RT Polyhedra [(UO2)4Cl2O2( OH2)(H2O)6](H 11.64 10.1 10.20 105.7 No No Finite Cl 2O)4 5 01 6 90 7 90 Aberg 1976 data data Clusters Rb4[(UO2)4O2C l8(H2O)2](H2O 8.09 21.73 111.7 soluti Finite Cl )2 8.54 6 5 90 4 90 Perrin 1977 on RT Clusters K2[(UO2)4Cl4O 2(OH)2(H2O)4] 12.3 soluti Finite Cl (H2O)2 12.15 3 8.026 110.5 96.3 138.71 Perrin 1977 on RT Clusters

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Cs0.9[(UO2)OCl 4.11 105.2 solid 501- Finite Cl 0.9] 8.734 8 7.718 90 6 90 Allpress 1964 state 1000 Clusters [(UO2)(OH)Cl(H 17.74 6.13 10.72 soluti Finite Cl 2O)2] 3 6 5 90 95.52 90 Aberg 1969 on RT Clusters [(UO2)(ClO4)2] 5.454 18.1 10.32 90.01 soluti Finite Cl (H2O)3 4 109 46 90 6 90 Fischer 2003 on RT Clusters 8.53 soluti Infinite Cl [(UO2)Cl2H2O] 5.828 4 5.557 90 97.79 90 Taylor 1974 on RT Chains solid Infinite Cl (UO2)Cl2 15.25 17.8 3.996 90 90 90 Taylor 1974 state 0-500 Frameworks (UO2)2(OH)2Cl 10.71 6.12 17.66 soluti Finite Cl 2(H2O)4 2 12 2 90 95.47 90 Huys 2010 on 31-150 Clusters 9.515 9.51 5.613 No No Cl La3 (U O6 Cl3) 5 55 2 90 90 120 1993 data data No data

222 9.395 9.39 No No Cl Pr3 (U O6 Cl3) 7 57 5.547 90 90 120 1993 data data No data 9.366 9.36 No No Cl Nd3 (U O6 Cl3) 8 68 5.53 90 90 120 1993 data data No data Rb2 (U O2 Cl4) 6.92 102.1 No No Cl (H2 O)2 6.795 9 7.457 91.96 3 118.82 1996 data data No data Cs3 ((U O2)3 O2 (O H)3)2 Cl (H2 15.47 7.23 12.06 No No Cl O)3 1 9 4 90 90 90 2001 data data No data (Li (H2 O)2) ((U O2)2 Cl3 O (H2 8.110 8.62 8.739 112.22 96.37 No No Cl O)) 1 07 8 8 8 93.665 2002 data data No data 5.791 5.80 90.14 solid 501- Infinite Co Sr2(CoUO6) 6 34 8.179 90 55 90 Pinacca 2005 state 1000 Frameworks Co(UO2)(SO4)2 8.29 11.28 soluti Co (H2O)5 6.452 5 8 90 90 90 Alekseev 2005 on RT Sheets

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Cs2[(UO2)4(Co( H2O)2)2(HPO4) 18.05 10.7 15.35 99.24 soluti 151- Infinite Co (PO4)] 51 478 04 90 2 90 Shvareva 2006 on 300 Frameworks K8[(UO2)(CrO4 7.039 9.73 9.756 105.84 97.99 Krivoviche soluti Finite Cr )4](NO3)2 7 41 8 6 2 93.271 v 2003 on RT Clusters Na4[(UO2)(CrO 7.154 8.44 11.51 Krivoviche solid Infinite Cr 4)3] 8 2 02 80.203 79.31 70.415 v 2003 state 0-500 Chains K5[(UO2)(CrO4 )3](NO3)(H2O) 6.111 12.1 27.46 Krivoviche soluti Infinite Cr 3 2 36 4 90 90 90 v 2003 on RT Chains [(UO2)(CrO4)(H 11.17 7.11 soluti Infinite Cr 2O)2](H2O)3.5 9 9 26.49 90 94.19 90 Serezhkin 1981 on RT Chains (UO2)(CrO4)(H 16.78 22.7 6.996 90.05 Krivoviche soluti Infinite Cr 2O)2 6 31 9 90 1 90 v 2003 on RT Chains

223 [(UO2)(CrO4)(H 9.720 7.16 11.09 92.38 Krivoviche soluti Infinite Cr 2O)2](H2O) 6 17 09 90 8 90 v 2003 on RT Chains [(UO2)(CrO4)(H 31.39 7.17 16.24 97.51 Krivoviche soluti Infinite Cr 2O)2]4(H2O)9 7 01 8 90 5 90 v 2003 on 31-150 Chains K2[UO2(CrO4)( 11.13 7.28 15.56 107.9 soluti 151- Infinite Cr IO3)2] 37 84 61 90 77 90 Sykora 2002 on 300 Chains Rb2[UO2(CrO4) 11.34 7.32 15.93 108.1 soluti 151- Infinite Cr (IO3)2] 63 63 32 90 73 90 Sykora 2002 on 300 Chains Cs2[UO2(CrO4) 7.392 8.13 22.12 90.64 soluti 151- Infinite Cr (IO3)2] 9 46 6 90 7 90 Sykora 2002 on 300 Chains Rb[UO2(CrO4)( 7.313 8.05 87.07 soluti 151- Infinite Cr IO3)(H2O)] 3 61 8.487 88.74 5 71.672 Sykora 2002 on 300 Chains Cs2[(UO2)(CrO 7.392 8.13 22.12 90.64 soluti 151- Infinite Cr 4)(IO3)2] 9 46 6 90 7 90 Sykora 2002 on 300 Chains Rb2[(UO2)(Mo 10.9 13.67 soluti Cr O4)2](H2O) 7.967 56 9 90 96.69 90 Khrustalev 2000 on RT Sheets - V

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe K2[(UO2)2(CrO 4)3(H2O)2](H2 10.74 14.5 14.13 108.1 Krivoviche soluti Cr O)4 17 29 87 90 35 90 v 2003 on RT Sheets - V K4[(UO2)3(CrO 8.233 18.8 21.24 89.97 Krivoviche soluti Cr 4)5](H2O)8 6 042 13 90 9 90 v 2003 on RT Sheets - V Mg2[(UO2)3(Cr 19.92 21.0 18.49 Krivoviche soluti Cr O4)5](H2O)17 06 526 66 90 90 90 v 2003 on 31-150 Sheets - V Ca2[(UO2)3(Cr 11.03 17.5 11.50 118.1 Krivoviche soluti Cr O4)5](H2O)19 59 364 56 90 78 90 v 2003 on 31-150 Sheets - V K[(UO2)(CrO4)( 13.29 9.47 13.13 104.1 No No Cr OH)](H2O)1.5 2 7 7 90 2 90 Serezhkina 1990 data data Sheets - V K2[(UO2)2(Cr2 6.548 8.35 105.0 soluti 151- Cr O8)] 3 48 10.42 90 4 90 Locock 2004 on 300 Sheets - TSP Rb2[(UO2)2(Cr 6.867 8.35 10.46 106.0 soluti 151-

224 Cr 2O8)] 7 99 25 90 04 90 Locock 2004 on 300 Sheets - TSP Cs2[(UO2)2(Cr2 7.264 8.38 106.3 soluti 151- Cr O8)] 3 03 10.51 90 99 90 Locock 2004 on 300 Sheets - TSP Mg2[(UO2)2(Cr 10.58 15.1 8.142 soluti 151- Cr 2O8)](H2O)4 25 34 5 90 90 90 Locock 2004 on 300 Sheets - TSP Sr[(UO2)2(CrO4 )2(OH)2](H2O) 9.96 11.60 No No Sheets - Cr 8 8.923 5 2 106.63 99.09 97.26 Serezhkin 1982 data data TSPH 4.98 soluti Infinite Cr Cr2UO6 4.988 8 4.62 90 90 120 Hoekstra 1971 on 300+ Frameworks K6[(UO2)4(CrO 10.95 22.5 7.955 soluti 151- Cr 4)7](H2O)6 83 819 2 90 90 90 Sykora 2004 on 300 Sheets No No Cr U(Cr2O6) 4.99 4.99 4.622 90 90 120 Collomb 1976 data data No data Cs3[(UO2)12O7 14.12 14.1 22.40 soluti 151- Cs (OH)13](H2O)3 41 241 73 90 90 120 Hill 1999 on 300 Sheets - TP α- 14.52 4.26 112.9 van solid 501- Cs Cs2[(UO2)2O3] 8 38 7.605 90 3 90 Egmond 1976 state 1000 Sheets - TP

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe β- 14.61 4.31 113.7 van solid 501- Cs Cs2[(UO2)2O3] 5 99 7.465 90 8 90 Egmond 1976 state 1000 Sheets - TP 18.77 14.95 van solid 501- Cs Cs4[(UO2)5O7] 6 7.07 8 90 90 90 Egmond 1976 state 1000 Sheets - TSP Cs2(U2O7)(D2O 14.53 4.27 7.601 113.0 soluti 151- Cs )0.444 14 39 1 90 2 90 Mijlhoff 1993 on 300 Sheets - H Cs(UO2)9U3O1 11.39 11.3 43.72 soluti 151- Infinite Cs 6(OH)5 52 952 2 90 90 120 Kubatko 2006 on 300 Frameworks 7.61 109.46 125.1 solid 501- Cu [(UO2)(CuO4)] 6.516 4 5.615 4 8 89.993 Dickens 1993 state 1000 Sheets - TSP Vandenb [(UO2)Cu(OH)4 5.44 Rosenzwei natura Cu randeite ] 7.855 9 6.089 91.44 101.9 89.2 g 1977 l Sheets - TSP 4.95 118.8 No No Infinite Cu Cu(UO2)O2 5.475 7 6.569 90 7 90 Siegel 1968 data data Frameworks

225 Cs3.14[(UO2)3C uH3.86(PO4)5]( 7.586 19.9 17.97 soluti 151- Infinite Cu H2O) 7 574 26 90 90 90 Shvareva 2006 on 300 Frameworks K2[(UO2)3F8(H 14.1 No No F 2 O)](H2O)3 8.39 2 13.66 90 90 90 Dao 1979 data data No data Cs2 (N H4) ((U 8.55 12.43 No No F O2)2 F7) 6.526 3 4 90 90 90 Ivanov 1980 data data No data Ni3 ((U O2)2 16.9 No No F F7)2 (H2 O)18 9.131 25 12.5 90 90 114.62 Ivanov 1981 data data No data (Na3 (U O2)2 7.17 No No F F7) (H2 O)6 6.997 6 8.63 77.84 113.3 104.95 Nguyen 1981 data data No data Ni U O2 F4 (H2 10.14 11.9 No No F O)7 1 01 9.51 90 90 96.8 Ivanov 1982 data data No data 9.15 No No F K3 (U O2 F5) 9.159 9 18.17 90 90 90 1986 data data No data ((U O2) F2 (H2 13.84 9.80 104.4 No No F O)) (H2 O)0.571 3 1 24.97 90 7 90 2002 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe (Fe,Mg)xPb8.57 [(UO2)18O18(O 20.93 16.34 115.3 natura Fe Richetite H)12]2(H2O)41 909 12.1 499 103.87 7 90.27 Burns 1998 l Sheets - TP 5.78 89.82 solid 501- Infinite Fe Sr2FeUO6 5.799 19 8.167 90 9 90 Pinacca 2007 state 1000 Frameworks Cs4[(UO2)2(Ga OH)2(PO4)4](H 18.87 9.51 14.00 109.6 soluti 151- Infinite Ga 2O) 16 05 7 90 5 90 Shvareva 2005 on 300 Frameworks Cs[(UO2)Ga(PO 7.776 8.50 8.911 70.56 soluti 151- Infinite Ga 4)2] 5 43 5 66.642 3 84.003 Shvareva 2005 on 300 Frameworks (UO2)2(GeO4)( 11.5 19.39 soluti Infinite Ge H2O)2 8.179 15 7 90 90 90 Legros 1975 on 31-150 Frameworks Na14[Na2(UO2) 2(GeW9O34)2]( 13.41 13.5 16.16 73.29 soluti Infinite

226 Ge H2O)42 8 3 7 85.215 4 64.937 Tan 2006 on 31-150 Frameworks Na14[Na2(UO2) 2(GeW9O34)2]( 13.52 13.5 15.77 100.95 104.4 soluti Infinite Ge H2O)48 8 78 1 2 77 105.604 Tan 2006 on 31-150 Frameworks Ag2[(UO2)3(Ge 10.04 7.46 17.77 soluti 151- Infinite Ge O4)2](H2O)2 62 99 63 90 90 90 Ling 2010 on 300 Frameworks Cs3(U5+UO4)(G 7.105 12.5 15.56 101.3 soluti Infinite Ge e2O7) 4 728 11 90 12 90 Lin 2008 on 300+ Frameworks Rb3(U5+UO4)( 6.975 12.2 15.39 100.5 soluti Infinite Ge Ge2O7) 5 284 91 90 6 90 Lin 2008 on 300+ Frameworks Cs6[(UO2)3(Ge 7.641 10.3 18.85 92.94 soluti Infinite Ge 2O7)2](H2O)4 7 281 45 90 1 90 Lin 2009 on 300+ Frameworks [Cu(H2O)4](UO 2HGeO4)2(2H2 7.14 soluti Ge 0) 17.66 8 6.817 90 112.8 90 Legros 1975 on 31-150 Sheets Cs2[(UO2)(Ge2 7.915 21.5 12.46 96.96 soluti 151- Infinite Ge O6)](H2O) 9 949 59 90 4 90 Ling 2010 on 300 Frameworks

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Ag[(UO2)2(HGe 7.124 10.7 14.02 soluti 151- Infinite Ge 2O7)](H2O) 1 71 4 90 90 90 Ling 2010 on 300 Frameworks 4.245 16.6 107.5 soluti Infinite I [UO2(IO3)2] 4 36 5.284 90 7 90 Bean 2001 on 300+ Chains K2[(UO2)3(IO3) 7.037 7.77 8.985 105.6 soluti Infinite I 4O2] 2 27 1 93.386 68 91.339 Bean 2001 on 300+ Chains Rb2[(UO2)3(IO 7.083 7.89 105.1 soluti 151- Infinite I 3)4O2] 4 35 9.092 91.741 1 92.214 Bean 2001 on 300 Chains Tl2[(UO2)3(IO3 7.060 7.94 9.017 105.5 soluti 151- Infinite I )4O2] 2 75 5 91.867 95 91.577 Bean 2001 on 300 Chains Ba[(UO2)2(IO3) 21.66 98.04 soluti 151- Infinite I 2O2](H2O) 8.062 6.94 5 90 9 90 Bean 2001 on 300 Chains Sr[(UO2)2(IO3) 6.94 21.43 99.32 soluti 151- Infinite I 2O2](H2O) 7.814 25 4 90 4 90 Bean 2001 on 300 Chains

227 Pb[(UO2)2(IO3) 7.844 6.93 99.06 soluti 151- Infinite I 2O2](H2O) 1 28 21.34 90 2 90 Bean 2001 on 300 Chains UO2(IO3)2(H2O 7.70 12.27 soluti I ) 8.452 7 1 90 90 90 Bean 2001 on 31-150 Sheets - V Ag4(UO2)4(IO3 8.05 18.33 100.7 soluti 151- I )2(IO4)2O2 15.04 1 2 90 38 90 Bean 2001 on 300 Sheets - Misc Cs[(UO2)3(HIO 6)(OH)(O)(H2O 13.09 10.0 11.03 102.0 soluti 151- Infinite I )](H2O)1.5 6 714 98 90 64 90 Sullens 2004 on 300 Frameworks K3[(UO2)2(IO3) 7.060 14.5 14.70 119.54 95.25 soluti 151- Infinite I 6](IO3)(H2O) 9 686 47 7 6 93.206 Sykora 2004 on 300 Chains 11.49 7.22 25.39 soluti 151- I K[(UO2)(IO3)3] 5 93 4 90 90 90 Shvareva 2005 on 300 Sheets Na2[(UO2)(IO3) 11.38 8.05 7.651 90.10 soluti I 4(H2O)] 1 47 5 90 2 90 Bray 2006 on 31-150 Sheets UO2(IO3)2(H2O 8.334 7.65 20.89 soluti 151- I )(HIO3)2 7 94 88 90 90 90 Ling 2007 on 300 Sheets

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Cs2 ((U O2)3 Cl2 (I O3) (O H) 8.271 12.4 17.11 No No I O2) (H2 O)2 5 73 7 90 90 90 2002 data data No data 6.192 6.19 5.337 soluti Isolated K K2Li4[UO6] 7 27 6 90 90 120 Wolf 1987 on 300+ Polyhedra 6.473 9.69 6.343 No No Finite K K8[(UO2)2O6] 8 79 8 101.17 102.3 109.02 Wolf 1986 data data Clusters K2(Ca0.65Sr0.3 Agrinieri 5)[(UO2)3O3(O 14.09 14.1 24.10 natura K te H)2]2(H2O)5 4 27 6 90 90 90 Cahill 2000 l Sheets - TP Comprei K2[(UO2)3O2(O 14.85 7.17 12.18 natura K gnacite H)3]2(H2O)7 91 47 71 90 90 90 Burns 1998 l Sheets - TP 109.6 solid 501- K K2[(UO2)2O3] 6.931 7.69 6.984 90 9 90 Saine 1989 state 1000 Sheets - TSP

228 K2[(UO2)5O8]( 19.5 solid 501- K UO2)2 6.945 33 7.215 90 90 90 Kovba 1972 state 1000 Sheets - TSP K5[(UO2)10O8( 13.17 20.8 13.43 106.3 soluti 151- K OH)9](H2O) 9 95 1 90 16 90 Burns 2000 on 300 Sheets - TSP solid K K2U2O7 3.96 3.96 19.82 90 90 120 Jove 1988 state 1000+ Sheets - H 4.332 4.33 13.13 soluti K K2(UO4) 1 21 82 90 90 90 Roof 2010 on 300+ Sheets 8.380 8.38 7.383 soluti Isolated Li Li6[UO6] 7 07 4 90 90 120 Wolf 1985 on 300+ Polyhedra 10.54 6.06 solid 501- Li Li2[(UO2)O2] 7 5 5.134 90 90 90 Gebert 1978 state 1000 Sheets - V 6.98 No No Infinite Mn Mn(UO2)O2 6.647 4 6.75 90 90 90 Bacmann 1966 data data Frameworks 5.853 8.27 solid 501- Infinite Mn Sr2MnUO6 7 8 90 90.014 90 Pinacca 2007 state 1000 Frameworks Cs6[(UO2)(MoO 11.61 12.5 14.46 102.71 95.28 Krivoviche solid 501- Finite Mo 4)4] 3 45 6 3 1 106.182 v 2002 state 1000 Clusters

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Rb6[(UO2)(Mo 17.31 11.5 13.91 127.6 Krivoviche solid 501- Finite Mo O4)4] 2 285 6 90 34 90 v 2002 state 1000 Clusters Na6[(UO2)(Mo 7.095 9.56 13.41 86.62 Krivoviche solid 501- Finite Mo O4)4] 8 6 5 73.692 1 82.94 v 2001 state 1000 Clusters Na3Tl3[(UO2)( 20.58 7.43 26.25 Krivoviche soluti Finite Mo MoO4)4] 23 91 14 90 90 90 v 2003 on 31-150 Clusters Cu4[(UO2)(Mo 6.11 104.1 Pushcharov natura Infinite Mo Deloryite O4)2](OH)6 19.94 6 5.52 90 8 90 sky 1996 l Chains Cu4[(UO2)(Mo 19.83 5.51 6.100 soluti 151- Infinite Mo O4)2](OH)6 92 08 9 90 90 104.477 Tali 1993 on 300 Chains Li2[(UO2)(MoO 5.345 5.82 8.265 108.26 100.5 Krivoviche solid 501- Infinite Mo 4)2] 5 97 2 7 66 104.121 v 2003 state 1000 Chains Na13-xTl3- x[(UO2)(MoO4) 19.79 7.19 22.88 97.82 Krivoviche soluti Infinite

229 Mo 3]4(H2O)6-x 42 13 35 90 8 90 v 2003 on 31-150 Chains Na2[(UO2)(Mo 8.902 11.5 13.81 107.7 Krivoviche soluti Infinite Mo O4)2](H2O)4 3 149 51 90 43 90 v 2003 on 31-150 Chains K2[UO2(MoO4) 11.37 7.29 15.71 108.1 soluti 151- Infinite Mo (IO3)2] 17 03 22 90 67 90 Sykora 2002 on 300 Chains Rb6[(UO2)2O( 10.15 10.1 13.11 76.55 Krivoviche solid 501- Infinite Mo MoO4)4] 67 816 29 76.921 3 65.243 v 2002 state 1000 Chains Na6[(UO2)2O( 8.16 79.36 Krivoviche solid 501- Infinite Mo MoO4)4] 7.637 4 8.746 72.329 4 65.795 v 2001 state 1000 Chains K6[(UO2)2O(M 7.828 7.82 10.30 73.13 Krivoviche solid 501- Infinite Mo oO4)4] 2 98 2 83.893 1 80.338 v 2001 state 1000 Chains Cs2[(UO2)(MoO 11.76 14.0 14.32 Krivoviche solid 501- Mo 4)2] 2 81 3 90 90 90 v 2004 state 1000 Sheets - V Cs2[(UO2)(MoO 11.0 13.99 95.15 Krivoviche soluti Mo 4)2](H2O) 8.222 993 92 90 5 90 v 2004 on 31-150 Sheets - V K2[(UO2)(MoO 12.26 13.4 12.85 solid 501- Mo 4)2](H2O) 9 68 7 90 95.08 90 Sadikov 1988 state 1000 Sheets - V

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Rb2[(UO2)(Mo 12.30 13.6 13.50 94.97 Krivoviche solid 501- Mo O4)2] 2 38 8 90 5 90 v 2002 state 1000 Sheets - V K2[(UO2)(MoO 10.9 13.55 Krivoviche soluti Mo 4)2](H2O) 7.893 07 8 90 98.7 90 v 2002 on 31-150 Sheets - V Tl2[(UO2)(CrO4 10.70 13.4 13.93 Krivoviche soluti 151- Mo )2] 34 252 64 90 90 90 v 2005 on 300 Sheets - V Na2[(UO2)(SeO 11.0 13.87 108.0 soluti Mo 4)2](H2O)4 8.65 03 9 90 8 90 Mikhailov 2001 on RT Sheets - V Na2[(UO2)(Mo 7.229 11.3 12.01 Krivoviche solid 501- Mo O4)2] 8 24 34 90 90 90 v 2002 state 1000 Sheets - V Mg(UO2)3(MoO 17.10 13.7 10.90 Tabachenk No No Mo 4)4(H2O)8 5 86 8 90 90 90 o 1983 data data Sheets - V Zn(UO2)3(MoO 17.05 13.7 10.91 Tabachenk No No Mo 4)4(H2O)8 6 86 9 90 90 90 o 1983 data data Sheets - V

230 β- Cs2(UO2)2(Mo 10.13 10.1 16.28 Krivoviche solid 501- Mo O4)3 67 367 31 90 90 90 v 2002 state 1000 Sheets - V Umohoit [(UO2)MoO4(H 6.374 7.52 14.62 Krivoviche natura Mo e 2O)](H2O) 8 87 8 82.64 85.95 89.91 v 2000 l Sheets - TSP [(UO2)Mo2O7( 12.7 11.52 Krivoviche soluti 151- Mo Iriginite H2O)2](H2O) 6.705 31 4 90 90 90 v 2000 on 300 Sheets - TSP [(UO2)Mo2O7( 35.07 6.71 11.51 90.06 Krivoviche soluti 151- Mo H2O)2] 1 7 3 90 9 90 v 2002 on 300 Sheets - TSP [Ca(UO2)(Mo4O 13.23 6.65 solid 501- Mo 7)2] 9 1 8.236 90 90.38 120.16 Lee 1987 state 1000 Sheets - TSP Tl2[(UO2)2O(M 8.252 28.5 9.155 104.1 Krivoviche solid 501- Mo oO5)] 7 081 5 90 22 90 v 2003 state 1000 Sheets - TSP K8(UO2)8(MoO 23.48 23.4 6.785 solid 501- Mo 5)3O6 8 88 7 90 90 90 Obbade 2003 state 1000 Sheets - TSP Cs4[(UO2)3O(M 7.89 81.26 Krivoviche solid 501- Mo oO4)2(MoO5)] 7.51 7 9.774 79.279 9 87.251 v 2002 state 1000 Sheets - TSP

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Ag10[(UO2)8O8 24.67 23.4 6.793 94.98 Krivoviche solid 501- Mo (Mo5O20)] 2 01 2 90 5 90 v 2003 state 1000 Sheets - TSP K2(UO2)2(MoO 8.249 15.3 8.351 104.7 solid 501- Mo 4)O2 8 37 4 90 48 90 Obbade 2003 state 1000 Sheets - TSP Ag6[(UO2)3O( 16.45 11.3 12.74 100.0 Krivoviche solid 501- Mo MoO4)5] 08 236 18 90 14 90 v 2002 state 1000 Sheets - Misc Cs2[(UO2)6(Mo 10.8 25.67 Krivoviche soluti 151- Infinite Mo O4)7(H2O)2] 13.99 08 1 90 90 90 v 2001 on 300 Frameworks (NH4)2[(UO2)6 (MoO4)7(H2O) 10.7 25.60 Krivoviche soluti 151- Infinite Mo 2] 13.97 47 7 90 90 90 v 2001 on 300 Frameworks Rb2[(UO2)6(Mo 13.96 10.7 25.57 Krivoviche soluti 151- Infinite Mo O4)7(H2O)2] 1 52 9 90 90 90 v 2002 on 300 Frameworks α-

231 Cs2(UO2)2(Mo 20.43 8.55 9.854 Krivoviche soluti 151- Infinite Mo O4)3 02 52 9 90 90 90 v 2002 on 300 Frameworks Rb2[(UO2)2(Mo 20.21 8.37 9.746 Krivoviche solid 501- Infinite Mo O4)3 4 44 4 90 90 90 v 2002 state 1000 Frameworks Tl2[(UO2)2(Mo 20.12 8.28 9.704 solid 501- Infinite Mo O4)3] 96 11 5 90 90 90 Nazarchuk 2005 state 1000 Frameworks Ba(UO2)3(MoO 17.79 11.9 Tabachenk No No Infinite Mo 4)4(H2O)4 7 75 23.33 90 90 90 o 1984 data data Frameworks α- (UO2)(MoO4)( 13.61 11.0 10.85 113.0 soluti Infinite Mo H2O)2 2 05 4 90 5 90 Serezhkin 1980 on RT Frameworks Sr(UO2)6(MoO 11.16 20.2 24.06 Tabachenk No No Infinite Mo 4)7(H2O)15 6 81 1 90 90 90 o 1984 data data Frameworks Ca[(UO2)6(MoO 4)7(H2O)2](H2 11.36 20.0 23.83 No No Infinite Mo O)n 91 311 33 90 90 90 Nazarchuk 2005 data data Frameworks

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe (NH4)4[(UO2)5 (MoO4)7](H2O) 11.40 11.4 70.65 Krivoviche soluti 151- Infinite Mo 5 67 067 9 90 90 120 v 2003 on 300 Frameworks 5.48 13.59 104.5 solid 501- Infinite Mo (UO2)(MoO4) 7.202 4 9 90 4 90 Serezhkin 1980 state 1000 Frameworks Cs2[(UO2)O(Mo 12.01 12.4 17.91 solid 501- Mo O4)] 8 38 7 90 90 90 Alekseev 2007 state 1000 Sheets Li4[(UO2)10O1 7.942 19.9 10.07 90.57 solid 501- Infinite Mo 0(Mo2O8)] 6 895 96 90 5 90 Alekseev 2007 state 1000 Frameworks CsNa3[(UO2)4O 6.465 6.90 11.38 77.90 solid 501- Mo 4(Mo2O8)] 5 57 1 84.325 6 80.23 Nazarchuk 2009 state 1000 Sheets CsNa8[(UO2)8O 23.2 12.33 solid 501- Infinite Mo 8(Mo5O20)] 6.846 855 73 90 90 90 Nazarchuk 2009 state 1000 Frameworks 15.3 104.2 solid 501-

232 Mo Rb2U2MoO10 8.542 6 8.436 90 79 90 Alekseev 2007 state 1000 Sheets (N H4)4 ((U O2)2 (H2 O)3 U Mo12 O42) (H2 11.42 14.3 16.49 No No Mo O)18 9 59 1 84.58 87.96 87.38 1984 data data No data Mg (U O2)6 (Mo 11.31 20.1 23.87 No No Mo O4)7 (H2 O)14 3 63 7 90 90 90 1984 data data No data (U O2) ((Mo O4) Umohoit (H2 O)) (H2 7.53 No No Mo e O)1.45 14.69 5 6.372 90.07 85.9 97.1 2000 data data No data Na3 Tl5 ((U O2) (Mo O4)3)2 (H2 10.76 11.9 12.89 No No Mo O)3 62 621 95 90 90 90 2003 data data No data Rb[(UO2)(NO3) 9.38 18.89 soluti Finite N 3] 9.384 4 9 90 90 120 Zalkin 1989 on RT Clusters K[(UO2)(NO3)3 13.48 9.58 7.956 116.1 Krivoviche soluti Finite N ] 77 43 4 90 24 90 v 2004 on RT Clusters

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Rb2[(UO2)(NO3 108.6 soluti Finite N )4] 6.42 7.82 12.79 90 8 90 Kapshukov 1971 on RT Clusters [(UO2)(NO3)2]( 13.19 8.03 11.46 No No Finite N H2O)6 7 5 7 90 90 90 Taylor 1965 data data Clusters [(UO2)(NO3)2]( 14.12 8.43 soluti Finite N H2O)2 4 2 7.028 90 108 90 Dalley 1971 on RT Clusters [(UO2)(NO3)2]( 7.035 7.17 10.08 82.04 soluti Finite N H2O)3 9 3 4 81.697 1 63.642 Hughes 2003 on RT Clusters [(UO2)(NO3)2( 7.179 8.95 14.30 99.40 solid Finite N H2O)2](H2O) 7 4 1 90 1 90 Shuvalov 2003 state 1000+ Clusters [(UO2)2(OH)2( 8.62 10.39 105.5 soluti Finite N NO3)2](H2O)4 8.622 8 3 109.57 6 99.65 Perrin 1976 on RT Clusters [(UO2)3O(OH)3 (H2O)6](NO3)( 11.2 12.34 No No Finite

233 N H2O)4 8.026 76 6 109.65 99.39 88.62 Aberg 1978 data data Clusters (NH4)3(H2O)2{ [(UO2)10O10(O H)][(UO4)(H2O 11.62 21.1 14.70 103.9 soluti 151- Infinite N )2]} 73 61 6 90 3 90 Li 2001 on 300 Frameworks Na ((U O2) (N 10.63 10.6 10.63 No No N O3)3) 24 324 24 90 90 90 2010 data data No data 7.557 7.55 4.641 solid 501- Infinite Na Na4[(UO2)O3] 1 71 1 90 90 90 Wolf 1986 state 1000 Chains β- 11.70 5.80 No No Na Na2[(UO2)O2] 8 5 5.97 90 90 90 Kovba 1971 data data Sheets - V Na2[(UO2)3O3( 7.047 11.4 12.02 soluti 151- Na OH)2] 6 126 74 90 90 90 Li 2001 on 300 Sheets - TP Na[(UO2)4O2(O 8.074 8.46 11.21 87.49 soluti Na H)5](H2O)2 6 33 81 80.398 2 71.308 Burns 2002 on 31-150 Sheets - TP No No Na (Na2U2O7)0.5 6.34 6.34 6.34 36.11 36.11 36.11 Kovba 1958 data data Sheets - H

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Na5[(UO2)3(O2 )4(OH)3](H2O) 23.63 15.8 13.95 soluti Na 13 15 862 18 90 90 90 Kubatko 2006 on RT Sheets 7.517 7.51 4.632 soluti Infinite Na Na4(UO5) 2 72 5 90 90 90 Roof 2010 on 300+ Chains K[(UO2)(NbO4) 11.3 15.25 solid Nb ] 7.579 21 9 90 90 90 Gasperin 1987 state 1000+ Sheets - TSP Cs2[(UO2)2(Nb 10.66 105.0 solid Nb 2O8)] 7.43 8.7 8 90 8 90 Gasperin 1987 state 1000+ Sheets - TSP 12.7 No No Nb [(UO2)Nb3O8] 7.38 8 15.96 90 90 90 Chevalier 1968 data data Sheets - H gamma- Rb(NbUO6)(H2 11.2 solid Nb O) 7.614 19 16.51 90 90 90 Alekseev 2005 state 1000+ Sheets

234 10.30 7.58 13.40 solid Infinite Nb K(NbUO6) 75 82 3 90 90 90 Surble 2006 state 1000+ Frameworks 10.30 6.44 7.560 100.6 solid Nb Li(NbUO6) 91 12 2 90 52 90 Surble 2006 state 1000+ Sheets (Cs0.077Na0.92 10.27 7.62 13.45 solid Infinite Nb 3)(NbUO6) 2 8 1 90 90 90 Surble 2006 state 1000+ Frameworks Cs9[(UO2)8O4( NbO5)(Nb2O8) 16.72 14.9 20.15 110.5 solid Nb 2] 9 33 5 90 9 90 Saad 2008 state 1000+ Sheets (Cs.75 K.25) 10.9 13.60 No No Nb (Nb Ti) U2 O11 7.63 23 9 90 90 90 1986 data data No data Tl Nb2 U2 10.3 13.94 No No Nb O11.5 7.713 29 7 90 90 90 1987 data data No data Cs0.5 (Nb U 13.95 10.6 No No Nb O5.75) 2 07 7.748 90 90 90 2006 data data No data Rb0.5 (Nb U 10.43 7.68 13.85 No No Nb O5.75) 2 1 3 90 90 90 2006 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe 5.780 5.77 8.156 89.83 solid 501- Infinite Ni Sr2NiUO6 9 52 2 90 7 90 Pinacca 2007 state 1000 Frameworks (Ni(H2O)4)3[U( OH)(H2O)(UO2) 10.5 12.09 102.9 soluti 151- Infinite Ni 8O12(OH)3] 8.627 66 1 110.59 6 105.5 Rivenet 2009 on 300 Frameworks Ca2 (U O2) 12.1 12.31 No No O2 (O2)3 (H2 O)9 9.576 72 4 90 90 90 2007 data data No data K6 ((U O2) (O2)2 (O H))2 15.07 6.66 23.52 No No O2 (H2 O)7 8 9 6 90 90 90 2007 data data No data Na4 (U O2) 6.788 16.0 16.56 91.91 No No O2 (O2)3 (H2 O)12 3 005 24 90 7 90 2007 data data No data Na2 Rb4 (U O2)2 (O2)5 (H2 16.8 23.28 No No

235 O2 O)14 6.808 88 6 90 90 90 2007 data data No data Na8 ((U O2) (O2) (O H) 36.87 24.6 25.81 132.9 No No O2 O0.2)40 6 682 52 90 3 90 2008 data data No data K6 Li19 (Li (H2 O) K4 (H2 O)3 ((U O2)4 (O2)4 (H2 O)2)2 (P O3 O H)2 P6 W36 29.35 26.7 32.22 100.2 No No O2 O136) (H2 O)74 3 06 9 90 88 90 2008 data data No data Na6 ((U O2) (O2)2 (O H)2) (O H)2 (H2 13.35 5.85 15.94 112.2 No No O2 O)14 7 21 8 90 92 90 2008 data data No data K6 ((U O2)2 (O2) (C2 O4)4) 17.31 12.0 13.90 111.9 No No O2 (H2 O)4 2 841 4 90 17 90 2009 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe K10 ((U O2) (O2) (C2 O4))5 10.29 19.5 27.00 No No O2 (H2 O)13 49 235 32 90 90 90 2009 data data No data Na12 ((U O2) (O2) (C2 O4))6 18.62 26.6 No No O2 (H2 O)29 5 52 15.66 90 90 90 2009 data data No data (U O4 Na8.88 Cs4 (H2 O)9 (U O2)16 (O2)24 (O H)8) (H2 20.54 20.5 No No O2 O)46 68 468 40.71 90 90 90 2009 data data No data K22 (H2 O)55 (U O2) (O2)3 ((U O2)20 (O 36.34 15.9 37.78 114.1 No No

236 O2 H)16 (O2)28) 6 629 8 90 67 90 2009 data data No data Cs6.82 Na18 (U

O2)2 (O2)5 ((U O2)24 (O2)36 (O H)12) (H2 20.36 19.7 32.86 124.9 No No O2 O)66 9 6 4 90 78 90 2009 data data No data K2 (Mg (H2 O)6)4 ((U O2)3 6.555 8.28 18.14 93.35 No No O2 (O2)8) (H2 O)2 4 65 6 95.064 9 94.77 2009 data data No data Li48 K12 (U O2 (O2) (O H))60 37.88 37.8 37.88 No No O2 (H2 O)273 4 84 4 90 90 90 2009 data data No data K22 Na22 (U O2 (O2)1.5)44 (H2 20.92 20.9 77.81 No No O2 O)113 4 24 4 90 90 120 2009 data data No data Li36 ((U O2)36 (O2)41 (O 19.86 23.3 30.96 No No O2 H)26) (H2 O)42 1 69 4 77.897 88.57 89.136 2009 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe (NH4)[(UO2)(C 10.03 11.5 14.21 101.4 No No Ox 2O4)3] 1 19 3 90 6 90 Alcock 1973 data data No data (UO2)(C2O4)(H 17.0 No No Ox 2O)3 5.623 65 9.451 90 98.74 90 Jayadeyan 1972 data data No data (NH4)2[(UO2)( 107.8 No No Ox C2O4)2] 12.91 7.2 6.31 110.56 5 84.25 Alcock 1973 data data No data K2[(UO2)2(C2O 19.6 No No Ox 4)3(H2O)4] 8.85 7 5.37 90 91.5 90 Jayadeyan 1975 data data No data K6[(UO2)2(C2O 10.10 10.9 10.02 No No Ox 4)5(H2O)10] 3 44 1 121.4 104.7 63.8 Legros 1976 data data No data (U O2) (C4 O4) 11.2 10.53 No No Ox (H2 O) 5.676 89 6 90 90 90 1982 data data No data (N H4)2 (C (N H2)3)4 ((C2

237 O4) ((U O2) (C2 O4)2)2) (H2 10.1 13.88 No No Ox O)2 6.938 45 8 100.34 92.57 102.25 1998 data data No data (U O2 (C2 O4) (H2 O))2 (H2 16.9 No No Ox O)4 5.603 86 9.415 90 98.89 90 1999 data data No data Cs2 ((U O2) (C2 13.9 No No Ox O4) (Se O4)) 6.965 03 23.41 90 91.79 90 2000 data data No data Cs4 (U O2 (C2 O4)2 (S O4)) 21.1 21.49 No No Ox (H2 O)2.7 9.546 19 9 90 90 90 2000 data data No data (C (N H2)3)2 (U O2 (C2 O4)2 (C O (N H2)2)) (H2 9.85 14.40 No No Ox O) 6.907 2 8 74.2 80.69 74.51 2002 data data No data K2 ((U O2) (C2 O4)2 (C O (N 24.03 No No Ox H2)2)) (H2 O) 8.831 6.5 3 90 95.83 90 2002 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Na4 ((U O2)2 O2 (C2 O4)4 (H2 O)6) (H2 7.56 15.40 No No Ox O)2 6.938 6 9 94.76 96.38 111.67 2002 data data No data (N H4) ((U O2)2 (C2 O4)2 (O H)) 13.6 No No Ox (H2 O)2 5.65 28 9.498 90 90.64 90 2003 data data No data Na2 ((U O2)4 (C2 O4)5 (H2 11.3 14.62 No No Ox O)2) (H2 O)8 5.585 59 4 98.03 99 103.86 2003 data data No data (N H4) ((U O2) (C2 O4) (N C S)) 13.1 No No Ox (H2 O)2 9.129 02 8.981 90 99.19 90 2003 data data No data (C (N H2)3)3 (U

238 O2 (C2 O4)2 (N 14.6 10.22 106.7 No No Ox C S)) 6.966 21 4 90 2 90 2004 data data No data Ba2 (C (N H2)3) ((U O2)2 (C2 O4)4 (N C S) 22.4 18.95 No No Ox (H2 O)) (H2 O)7 8.123 1 6 90 97.84 90 2004 data data No data (N H4)4 ((U O2)2 (C2 O4)3 (N C S)2) (H2 8.83 No No Ox O)2 7.786 9 9.465 108.3 92.18 92.73 2004 data data No data Ba (U O2) (C2 14.41 10.8 17.48 No No Ox O4)2 (H2 O)5 2 91 2 90 90.1 90 2004 data data No data K2 (U O2) (C2 O4) (S O4) (H2 9.54 11.84 No No Ox O)3 5.743 4 5 89.49 84.95 83.01 2004 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe (C (N H2)3)2 ((U O2) (C2 O4)2 (H2 O)) 11.3 10.84 100.7 No No Ox (H2 O) 7.002 67 6 90 1 90 2005 data data No data (C2 H5)12 N4 H4 (U O2)2 C2 O4 (N C S)6 H2 14.84 27.3 14.07 113.3 No No Ox O 22 85 4 90 97 90 2005 data data No data (U O2)2 (C2 O4) 5.54 94.38 No No Ox (O H)2 (H2 O)2 6.097 76 7.806 89.353 7 97.646 2005 data data No data (U O2)2 (C2 O4) 8.22 10.77 95.81 No No Ox (O H)2 (H2 O)2 12.18 3 7 90 7 90 2005 data data No data ((U O2)2 (C2 O4) (O H)2 (H2 5.509 15.1 13.39 93.92 No No

239 Ox O)2) (H2 O) 5 95 8 90 7 90 2005 data data No data (U O2)2 (C2 O4) 5.535 6.08 7.768 89.77 No No Ox (O H)2 (H2 O)2 3 66 6 85.641 4 82.509 2006 data data No data (U O2) (C2 O4) 5.592 16.9 9.359 99.53 No No Ox (H2 O)3 1 931 4 90 3 90 2006 data data No data K ((U O2)2 (C2 O4)2 (O H)) (H2 5.642 13.7 9.266 98.74 No No Ox O)2 7 123 9 90 9 90 2006 data data No data Rb ((U O2)2 (C2 O4)2 (O H)) (H2 5.622 13.8 9.330 98.15 No No Ox O)2 5 339 8 90 9 90 2006 data data No data Cs ((U O2)2 (C2 O4)2 (O H)) (H2 5.468 13.5 9.540 97.58 No No Ox O) 8 71 8 90 3 90 2006 data data No data K3 ((U O2) (C2 O4)2 (N C S)) 10.67 12.0 13.85 110.1 No No Ox (H2 O)3 3 41 6 90 8 90 2006 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe (N H4) (C N3 H6)2 ((U O2) (C2 O4)2 (N C 13.4 23.08 No No Ox S)) (H2 O)2 6.668 63 6 90 90 90 2006 data data No data (U O2)2 (C2 O4)2 (O H) Na 9.150 13.1 11.69 No No Ox (H2 O)2 6 912 1 90 90 90 2007 data data No data Rb (U O2 (C2 O4) (N C S)) (H2 9.062 13.1 8.920 98.89 No No Ox O)0.5 4 242 4 90 7 90 2008 data data No data Cs (U O2 (C2 O4) (N C S)) (H2 9.317 13.2 9.115 101.0 No No Ox O)0.5 1 987 1 90 86 90 2008 data data No data Cs4 ((U O2)2

240 (C2 O4) (S O4)2 (N C S)2) (H2 12.01 18.6 6.757 No No

Ox O)4 77 182 3 90 90 90 2008 data data No data (N H4)4 ((U O2)2 (C2 O4) (S O4)2 (N C S)2) 11.65 18.3 6.721 No No Ox (H2 O)6 39 791 6 90 90 90 2008 data data No data Ba3 (U O2 (C2 O4)2 (N C S))2 16.25 22.2 39.03 No No Ox (H2 O)9 3 45 1 90 90 90 2008 data data No data K4 ((U O2)2 (C2 O4)3 (N C S)2) 8.022 14.9 11.16 98.29 No No Ox (H2 O)4 6 493 7 90 9 90 2008 data data No data Li (H3 O) (U O2 (C2 O4)2 (H2 7.168 29.6 No No Ox O)) (H2 O) 2 39 6.677 90 112.3 90 2009 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe K8 ((U O2)2 (C2 O4)2 (Se O4)4) 14.92 15.31 109.1 No No Ox (H2 O )2 9 7.28 65 90 88 90 2009 data data No data 13.71 12.3 solid 501- P Pb3[(UO2)O3] 9 51 8.213 90 90 90 Sterns 1986 state 1000 No data Cu2[UO2(PO4)2 5.75 5.027 107.2 solid Infinite P ] 14.04 95 8 90 4 90 Guesdon 2002 state 1000+ Chains [(UO2)(H2PO4) 10.81 13.8 105.6 Krogh- No No Infinite P 2(H2O)](H2O)2 6 96 7.481 90 5 90 Andersen 1985 data data Chains Parsonit Pb2[(UO2)(PO4 10.3 101.26 98.17 natura Infinite P e )2] 6.842 83 6.67 5 4 86.378 Burns 2000 l Chains Meta- uranocir Ba[(UO2)(PO4)] 9.88 16.86 Khosrawan soluti P cite 2(H2O)6 9.789 2 8 90 90 89.95 -Sazedj 1982 on 31-150 Sheets - V

241 Threadg Al[(UO2)(PO4)] 20.16 9.84 19.71 110.7 Khosrawan natura P oldite 2(OH)(H2O)8 8 7 9 90 1 90 -Sazedj 1982 l Sheets - V Meta- Ca[(UO2)(PO4)] No No P autunite 2(H2O)6 6.96 6.96 8.4 90 90 90 Makarov 1960 data data Sheets - V Ca[(UO2)(PO4)] 14.01 20.7 6.995 soluti P Autunite 2(H2O)11 35 121 9 90 90 90 Locock 2003 on RT Sheets - V Mg[(UO2)(PO4) 19.9 135.1 natura P Saleeite ]2(H2O)10 6.951 47 9.896 90 7 90 Miller 1986 l Sheets - V Torberni Cu[(UO2)(PO4)] 7.026 7.02 20.80 soluti P te 2(H2O)12 7 67 7 90 90 90 Locock 2003 on 0-20 Sheets - V Metatorb Cu[(UO2)(PO4)] 6.975 6.97 17.34 soluti P ernite 2(H2O)8 6 56 9 90 90 90 Locock 2003 on RT Sheets - V K[(UO2)(PO4)]( 6.993 6.99 17.78 soluti P D2O)3 79 379 397 90 90 90 Fitch 1991 on RT Sheets - V [(UO2)H(PO4)]( 6.99 17.49 soluti P H2O)4 6.995 5 1 90 90 90 Morosin 1978 on RT Sheets - V ND4[(UO2)(PO 7.022 7.02 18.09 soluti P 4)](D2O)3 1 21 119 90 90 90 Fitch 1983 on RT Sheets - V

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe K4[(UO2)(PO4) 6.98 11.86 solid 501- P 2] 6.985 5 5 90 90 90 Linde 1980 state 1000 Sheets - V Cs[(UO2)(PO3) 10.8 13.30 104.2 No No P 3] 6.988 38 9 90 5 90 Linde 1978 data data Sheets - V 20.8 8.694 No No P (UO2)H(PO3)3 9.811 14 7 90 90 94.09 Sarin 1983 data data Sheets - V CaCu(UO2)(PO4 12.78 6.99 13.00 natura P Ulrichite )2dot4H2O 4 6 7 90 91.92 90 Kolitsch 2001 l Sheets - TSP Na5.5(UO2)3(H 6.92 10.73 No No P 0.5PO4)(PO4)3 6.675 2 2 83.96 82.29 89.44 Gorbunova 1980 data data Sheets - TSP KCa(H3O)3(UO Phosphu 2)[(UO2)3(PO4) 15.89 13.7 natura Sheets - P ranylite 2O2]2(H2O)8 9 4 17.3 90 90 90 Demartin 1991 l TSPH Al[(UO2)3(PO4) 13.70 16.8 natura Sheets -

242 P Upalite 2O(OH)](H2O)7 4 2 9.332 90 111.5 90 Piret 1983 l TSPH Nd[(UO2)3(PO4 Francoisi )2O(OH)](H2O) 15.6 13.66 112.7 natura Sheets - P te-Nd 6 9.298 05 8 90 7 90 Piret 1988 l TSPH Pb3[h(UO2)3O2 Dewindti (PO4)2]2(H2O) 16.03 17.2 13.60 natura Sheets - P te 12 1 64 5 90 90 90 Piret 1990 l TSPH U(OH)4[(UO2)3 Vanmeer (PO4)2(OH)2]( 16.7 natura Sheets - P sscheite H2O)4 17.06 6 7.023 90 90 90 Piret 1982 l TSPH Dumonti Pb2[(UO2)3(PO 16.8 109.0 natura Sheets - P te 4)2O2](H2O)5 8.118 19 6.983 90 3 90 Piret 1988 l TSPH Ca2[(UO2)3(PO Phurcalit 4)2(OH)2](OH) 17.41 16.0 13.59 natura Sheets - P e 2(H2O)4 5 35 8 90 90 90 Atencio 1991 l TSPH Al2[(UO2)3(PO Phuralu 4)2(OH)2](OH) 13.83 20.9 112.4 natura Sheets - P mite 4(H2O)10 6 18 9.428 90 4 90 Piret 1979 l TSPH

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe AlTh(UO2)[(UO 2)3(PO4)2O(OH Althupit )]2(OH)3(H2O) 10.95 18.5 13.50 natura Sheets - P e 15 3 67 4 72.64 68.2 84.21 Piret 1987 l TSPH Ca2Ba4[(UO2)3 Bergenit O2(PO4)2]3(H2 10.09 17.2 17.35 113.6 natura Sheets - P e O)16 2 45 5 90 78 90 Locock 2003 l TSPH 5.46 solid Infinite P UO3HP 7.511 6 5.224 90 90 90 Siegel 1966 state 1000+ Frameworks (UO2)3(PO4)2( 17.0 13.17 soluti Infinite P H2O)4 7.063 22 2 90 90 90 Locock 2002 on 31-150 Frameworks Cs2(UO2)[(UO2 )(PO4)]4(H2O) 14.85 13.8 12.98 soluti 151- Infinite P 2 42 792 73 90 90 90 Locock 2002 on 300 Frameworks

243 Rb2(UO2)[(UO2 )(PO4)]4(H2O) 13.8 13.05 soluti 151- Infinite P 2 15.72 39 1 90.385 90 90 Locock 2002 on 300 Frameworks K2(UO2)[(UO2) 15.25 13.8 13.00 soluti 151- Infinite P (PO4)]4(H2O)2 66 313 69 91.76 90 90 Locock 2002 on 300 Frameworks Na2(UO2)(P2O 13.25 8.12 solid 501- Infinite P 7) 9 7 6.973 90 90 90 Linde 1984 state 1000 Frameworks [(UO2)3(PO4)O (OH)(H2O)2](H 14.01 14.0 13.08 soluti 151- Infinite P 2O) 53 153 33 90 90 90 Burns 2004 on 300 Frameworks U4+(UO2)(PO4) 8.821 9.21 5.477 102.62 97.74 solid Infinite P 2 2 73 2 2 8 102.459 Benard 1994 state 1000+ Frameworks Mn[(UO2)(PO4) 6.965 20.3 6.977 91.01 soluti P 2](H2O)10 6 768 5 90 9 90 Locock 2004 on RT Sheets Co[(UO2)(PO4) 19.9 soluti P 2](H2O)10 6.949 348 6.962 90 90.44 90 Locock 2004 on RT Sheets Ni[(UO2)(PO4) 6.996 7.00 11.17 82.18 soluti P 2](H2O)12 2 12 1 81.591 9 88.721 Locock 2004 on RT Sheets

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Ni[(UO2)(PO4) 6.950 19.8 6.971 90.41 soluti P 2](H2O)10 6 215 1 90 8 90 Locock 2004 on RT Sheets Rb[(UO2)(PO4) 7.010 7.01 17.97 soluti P ](H2O)3 6 06 72 90 90 90 Locock 2004 on RT Sheets Ag[(UO2)(PO4)] 6.933 6.93 16.93 soluti P (H2O)3 2 32 13 90 90 90 Locock 2004 on RT Sheets Tl[(UO2)(PO4)] 7.01 soluti P (H2O)3 7.019 9 17.98 90 90 90 Locock 2004 on RT Sheets Cs2[(UO2)(PO4 9.871 9.95 17.64 90.40 soluti P )]2(H2O)5 6 5 65 90 2 90 Locock 2004 on RT Sheets Na[(UO2)(PO4) 6.961 6.96 17.26 soluti P ](H2O)3 6 16 77 90 90 90 Locock 2004 on RT Sheets Li[(UO2)(PO4)] 6.955 6.95 9.138 soluti P (H2O)4 5 55 9 90 90 90 Locock 2004 on RT Sheets

244 Meta- uranocir Ba[(UO2)(PO4)] 16.8 natura P cite II 2(H2O)6 9.882 68 9.789 90 90.52 90 Barinova 2005 l Sheets Al0.86[(UO2)(P uranosp O4)]2(H2O)20. 7.00 7.049 natura P athite 42F0.58 30.02 84 2 90 90 90 Locock 2005 l Sheets Al0.67[(UO2)(P O4)]2(H2O)15. 13.7 14.02 89.67 natura P 5 7.002 12 43 78.418 6 81.863 Locock 2005 l Sheets Ba[(UO2)(PO4)] 17.6 90.02 soluti P 2(H2O)7 6.943 34 6.952 90 3 90 Locock 2005 on 31-150 Sheets Sr[(UO2)(PO4)] 14.04 21.0 soluti P 2(H2O)11 2 08 6.997 90 90 90 Locock 2005 on RT Sheets Cs(UO2)F(HPO4 25.65 6.03 9.207 soluti 151- P )(H2O)0.5 6 94 2 90 90 90 Ok 2006 on 300 Sheets Rb1.08(UO2)F( 17.71 6.87 12.13 soluti 151- P HPO4) 9 71 9 90 90 90 Ok 2006 on 300 Sheets

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe K(UO2)F(HPO4) 6.788 8.70 soluti 151- P (H2O) 5 24 12.02 90 94.09 90 Ok 2006 on 300 Sheets K2(UO2Co(PO4 8.105 17.0 7.825 105.5 soluti 151- Infinite P )2](H2O) 1 316 5 90 74 90 Yu 2008 on 300 Frameworks K[(UO2)2(P3O1 10.63 10.3 11.20 solid 501- Infinite P 0)] 2 25 9 90 90 90 Alekseev 2008 state 1000 Frameworks Li2[(UO2)3(P2 6.69 12.54 99.05 solid 501- Infinite P O7)2] 5.312 6 2 94.532 9 110.189 Alekseev 2008 state 1000 Frameworks a- 5.027 9.87 10.89 108.28 102.9 solid 501- Infinite P Li[(UO2)(PO4)] 1 99 2 2 93 104.13 Alekseev 2008 state 1000 Frameworks a- K[(UO2)(P3O9) 15.1 14.78 91.91 solid 501- Infinite P ] 8.497 15 9 90 1 90 Alekseev 2008 state 1000 Frameworks B-

245 K[(UO2)(P3O9) 14.84 8.60 14.95 95.82 solid 501- Infinite P ] 2 7 1 90 9 90 Alekseev 2008 state 1000 Frameworks Li3(UO2)7(PO4 9.930 9.93 14.57 solid 501- Infinite P )5O 5 05 41 90 90 90 Renard 2009 state 1000 Frameworks Li(UO2)4(PO4) 9.882 9.89 17.48 106.1 solid 501- Infinite P 3 9 09 71 90 98 90 Renard 2009 state 1000 Frameworks Li6[(UO2)12(P 26.96 7.06 19.63 126.8 solid 501- Infinite P O4)8(P4O13)] 3 3 9 90 9 90 Alekseev 2009 state 1000 Frameworks Li2(UO2)3(PO4 7.110 7.11 25.04 solid 501- Infinite P )2O 9 09 07 90 90 90 Renard 2009 state 1000 Frameworks Rb2[(UO2)3(P2 6.790 16.1 19.85 solid 501- Infinite P O7)(P4O12)] 6 55 6 90 97.48 90 Alekseev 2009 state 1000 Frameworks Rb4[(UO2)6(P2 12.9 32.23 90.11 solid 501- Infinite P O7)4(H2O)] 9.672 51 1 90 6 90 Alekseev 2009 state 1000 Frameworks CaNa(Fe3+)2H( Lakebog UO2)2(PO4)4(O 19.64 7.09 18.70 115.6 natura P aite H)2(H2O)8 41 58 29 90 92 90 Mills 2008 l Sheets

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Ba3(UO2)2(HP 9.505 8.69 10.54 97.31 soluti 151- P O4)2(PO4)2 5 87 4 90 4 90 Ling 2009 on 300 Sheets Cs2(UO2)2(PO4 14.17 19.53 soluti 151- P )2 62 8.93 47 90 90 90 Ling 2009 on 300 Sheets 6.666 8.26 10.79 92.06 soluti 151- P Ba(UO2)F(PO4) 8 59 45 90 2 90 Ling 2009 on 300 Sheets Cs2 (U O2) (P2 12.8 6.152 No No P O7) 12.67 07 2 90 90 90 Linde 1981 data data No data K2 (U O2 (H P 6.93 10.61 110.8 No No P O3)2) (H2 O)2 7.598 8 7 90 4 90 1985 data data No data Cs11 Eu4 (U O2)2 (P2 O7)6 13.62 13.6 29.95 No No P (P O4) 8 28 8 90 90 90 1997 data data No data (U O2) (H2 P 9.27 11.02 No No

246 P O2)2 (H2 O) 7.686 5 7 90 92.32 90 1999 data data No data (U O2 (H2 P 7.157 7.23 17.55 No No P O2)2) (H3 P O2) 2 63 4 90 90 90 1999 data data No data Moctezu 7.06 13.77 natura Infinite Pb mite PbTe[(UO2)O3] 7.813 1 5 90 93.71 90 Swihart 1993 l Chains 7.96 solid 501- Pb Pb[(UO2)O2] 5.536 8 8.212 90 90 90 Cremers 1986 state 1000 Sheets - V Pb[(UO2)3O3(O 12.24 7.00 90.40 natura Pb Masuyite H)2](H2O)3 1 8 6.983 90 2 90 Burns 1999 l Sheets - TP Fourmar Pb[(UO2)4O3(O 13.98 14.29 natura Pb ierite H)4](H2O)4 6 16.4 3 90 90 90 Piret 1985 l Sheets - TP Vandend Pb1.57[(UO2)1 riesschei 0O6(OH)11](H2 14.11 41.3 14.53 natura Pb te O)11 65 78 47 90 90 90 Burns 1997 l Sheets - TP Pb3[(UO2)6O8( 28.35 11.9 13.99 104.2 natura Pb Spriggite OH)2](H2O)3 5 9 8 90 48 90 Brugger 2004 l Sheets - TSP Pb2[(UO2)5O6( 10.70 14.53 116.8 natura Pb Sayrite OH)2](H2O)4 4 6.96 3 90 1 90 Piret 1983 l Sheets - TSP

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe [Pb3(UO2)11O1 28.45 8.37 solid 501- Pb 4] 9 9 6.765 90 90 90 Ijdo 1993 state 1000 Sheets - TSP Pb3[(UO2)8O8( 12.54 13.0 natura Pb Curite OH)6](H2O)3 8 26 8.389 90 90 90 Li 2000 l Sheets - TSP Pb6.16Ba0.36[( Wolsend UO2)14O19(OH 14.13 13.8 55.96 natura Pb orfite )4](H2O)12 1 85 9 90 90 90 Burns 1999 l Sheets - TSP Pb2(H2O)[(UO2 )10UO12(OH)6( 13.28 10.2 103.2 soluti 151- Infinite Pb H2O)2] 1 23 26.1 90 02 90 Li 2000 on 300 Frameworks 18.67 7.04 14.12 solid Rb Rb4[(UO2)5O7] 62 9 07 90 90 90 Saad 2009 state 1000+ Sheets Na(UO2)(ReO4) 12.31 22.6 109.3 soluti 151- Infinite Re 3(H2O)2 1 51 5.49 90 66 90 Karimova 2007 on 300 Frameworks

247 [(UO2)4(ReO4) 2O(OH)4(H2O) 7.884 11.4 16.97 89.38 soluti 151- Finite Re 7](H2O)5 4 429 6 83.195 7 85.289 Karimova 2007 on 300 Clusters (UO2)2(ReO4)4 5.277 15.47 99.13 soluti Re (H2O)3 1 13.1 6 107.18 1 94.114 Karimova 2007 on RT Sheets Na6[(UO2)(SO4 5.550 11.2 14.25 92.58 soluti Finite S )4](H2O)2 3 456 6 91.483 3 97.588 Hayden 2002 on 31-150 Clusters Na10[(UO2)(SO 4)4](SO4)2(H2 9.307 28.7 9.615 93.40 soluti Finite S O)3 2 064 2 90 1 90 Burns 2002 on 31-150 Clusters Kna5[(UO2)(SO 16.91 5.59 90.43 soluti Finite S 4)4(H2O) 7 99 35.34 90 7 90 Hayden 2002 on 31-150 Clusters K4[(UO2)(SO4) 13.05 No No Finite S 3] 3 23.2 9.379 90 90 90 Mikhailov 1977 data data Clusters Mn[(UO2)(SO4) 11.3 Tabachenk No No Infinite S 2(H2O)](H2O)4 6.506 68 8.338 90 90.79 90 o 1979 data data Chains [(UO2)(SO4)(H 10.7 Brandenbu No No Infinite S 2O)2](H2O)1.5 13.7 9 11.91 90 110.8 90 rg 1973 data data Chains

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe [(UO2)(SO4)(H 16.88 12.4 6.735 van der No No Infinite S 2O)2](H2O)0.5 7 92 4 90 90.88 90 Putten 1974 data data Chains [(UO2)(SO4)(H 11.22 21.18 soluti Infinite S 2O)2]2(H2O)3 7 6.79 6 90 90 90 Zalkin 1978 on RT Chains [(UO2)6(SO4)O 2(OH)6(H2O)6( 14.0 14.33 98.47 natura Infinite S H2O)8 8.896 29 9 96.61 2 99.802 Burns 2001 l Chains (NH4)2[(UO2)( SO4)2(H2O)](H 7.40 20.91 102.2 No No S 2O) 7.783 3 8 90 5 90 Niinisto 1978 data data Sheets - V Cu2[(UO2)3((S, Cr)O4)5](H2O) 18.05 19.9 20.55 Krivoviche soluti S 17 86 898 53 90 90 90 v 2004 on RT Sheets - V Cs2[(UO2)2(SO soluti

248 S 4)3] 9.62 9.62 8.13 90 90 90 Ross 1960 on RT Sheets - V [Co(H2O)6]3[(U O2)5(SO4)8(H2 27.15 9.98 22.78 106.5 Krivoviche No No S O)](H2O)5 97 58 03 90 2 90 v 2006 data data Sheets - V Mg[(UO2)(SO4) 11.33 7.71 21.70 102.2 No No S 2](H2O)11 4 5 9 90 2 90 Serezhkin 1981 data data Sheets - TP [(UO2)(SO4)2] 11.00 8.24 15.61 113.7 No No S H2(H2O)5 8 2 9 90 1 90 Alcock 1982 data data Sheets - TP K2[UO2(SO4)2] 13.80 11.5 No No S (H2O)2 6 77 7.292 90 90 90 Niinisto 1979 data data Sheets - TP K3(H2O)3[(UO2 )4(SO4)2O3(OH 8.752 13.9 17.69 104.1 soluti S Zippeite )] 4 197 72 90 78 90 Burns 2003 on 31-150 Sheets - TSP Na5(H2O)12[(U “Na O2)8(SO4)4O5( 17.64 14.6 17.69 104.4 soluti S zippeite” Oh)3] 25 272 22 90 61 90 Burns 2003 on 31-150 Sheets - TSP “Mg Mg(H2O)3.5[(U 8.651 14.1 17.72 104.1 soluti S zippeite” O2)2(SO4)O2] 4 938 11 90 31 90 Burns 2003 on 31-150 Sheets - TSP

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe “Zn Zn(H2O)3.5[(U 8.643 14.1 17.70 104.0 soluti S zippeite” O2)2(SO4)O2] 7 664 1 90 41 90 Burns 2003 on 31-150 Sheets - TSP “Co Co(H2O)3.5[(U 14.2 17.74 104.0 soluti S zippeite” O2)2(SO4)O2] 8.65 52 2 90 92 90 Burns 2003 on 31-150 Sheets - TSP Mg3(H2O)18[(U Marecott O2)4O3(OH)(SO 10.81 11.2 13.85 72.41 natura S ite 4)2]2(H2O)10 5 49 1 66.224 2 69.95 Brugger 2003 l Sheets - TSP (NH4)4(H2O)[( UO2)2(SO4)O2] 8.698 14.1 17.84 104.1 soluti S 2 7 66 7 90 17 90 Burns 2003 on 31-150 Sheets - TSP (NH4)2[(UO2)2 14.25 8.77 17.18 soluti S (SO4)O2] 2 48 63 90 90 90 Burns 2003 on 31-150 Sheets - TSP Mg2(H2O)11[(U 8.645 17.2 18.46 102.1 soluti S O2)2(SO4)O2]2 7 004 42 90 19 90 Burns 2003 on 31-150 Sheets - TSP

249 Cu[(UO2)2(SO4 Johannit )2(OH)2](H2O) 9.49 112.0 natura Sheets - S e 8 8.903 9 6.812 109.87 1 100.4 Mereiter 1982 l TSPH 5.71 12.82 102.9 Brandenbu solid Infinite S β-(UO2)(SO4) 6.76 1 4 90 1 90 rg 1978 state 0-500 Frameworks Rb2[(UO2)(SO4 13.45 11.4 soluti Infinite S )2(H2O)](H2O) 1 79 7.41 90 90 90 Serezhkina 2004 on RT Frameworks K2[(UO2)(SO4) 13.77 7.28 11.55 soluti S 2(H2O)2] 3 8 6 90 90 90 Alekseev 2006 on RT Sheets Cu6.5[(UO2)4O 4(SO4)2]2(OH) 10.02 10.8 13.39 natura S 5(H2O)25 7 22 6 87.97 109.2 90.89 Brugger 2006 l Sheets K(UO2)(SO4)(O 8.052 7.93 11.31 107.6 soluti Infinite S H)(H2O) 1 54 77 90 78 90 Forbes 2007 on 31-150 Chains K(UO2)(SO4)(O 8.445 10.8 13.54 soluti S H) 1 058 06 90 90 90 Forbes 2007 on 31-150 Sheets

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe K0.5Mn0.75[(U O2)2(SO4)O2]( 14.3 17.70 104.1 soluti 151- S H2O)3 8.661 75 5 90 2 90 Peeters 2008 on 300 Sheets K0.5Co0.75[(UO 2)2(SO4)O2](H 14.1 17.71 104.1 soluti 151- S 2O)3 8.651 88 3 90 4 90 Peeters 2008 on 300 Sheets K0.5Ni0.75[(UO 2)2(SO4)O2](H 14.0 104.1 soluti 151- S 2O)3 8.662 95 17.77 90 8 90 Peeters 2008 on 300 Sheets K0.5Zn0.75[(UO 2)2(SO4)O2](H 14.1 17.70 104.1 soluti 151- S 2O)3 8.65 8 9 90 4 90 Peeters 2008 on 300 Sheets (UO2)(SO4)(H2 12.4 16.82 90.78 soluti Infinite S O)2.5 6.726 21 7 90 1 90 Vlcek 2009 on RT Chains

250 K2 (U F2 O2) (S 9.263 8.67 11.01 No No S O4) H2 O 4 22 95 90 101.6 90 Alcock 1980 data data No data Zn (U O2)2 (S O4) (O H)4 (H2 17.7 14.18 No No S O)1.5 8.654 14 2 90 90 103.92 Spitsyn 1982 data data No data (N H4) ((U O2) 11.3 No No S (S O4) F) 8.681 19 6.729 90 90 90 1985 data data No data Rb2 ((U O2) (S O4) (C2 O4)) 17.0 No No S (H2 O) 9.72 37 6.852 90 90 90 1993 data data No data Rb (U O2 (S O4) 25.39 6.73 11.49 No No S F) 3 5 6 90 90 90 2002 data data No data 4.00 5.141 104.1 soluti 151- Sb [(UO2)(Sb2O4)] 13.49 34 9 90 65 90 Sykora 2004 on 300 Sheets - H 10.72 10.7 10.72 solid Infinite Sb Cs(SbUO6) 98 298 98 90 90 90 Knyazev 2009 state 1000+ Frameworks 14.7 No No Sb U F4 O (Sb F5)2 7.864 04 9.98 90 99.8 90 Bougon 1979 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe U F2 O2 (Sb 12.4 12.14 111.1 No No Sb F5)3 11.04 38 7 90 6 90 1982 data data No data Derriksit Cu4[(UO2)(SeO 19.0 natura Infinite Se e 3)2](OH)6 5.57 88 5.965 90 90 90 Ginderow 1983 l Chains [UO2(HSeO3)2( 12.5 Koskenlinn soluti Infinite Se H2O)] 9.924 46 6.324 90 98.09 90 a 1997 on 31-150 Chains [(UO2)(HSeO3) 12.5 No No Infinite Se 2(H2O)] 6.354 78 9.972 90 82.35 90 Mistryukov 1983 data data Chains Pb2Cu5[(UO2)( Demesm SeO3)3]2(OH)6 11.95 10.0 100.3 natura Infinite Se aekerite (H2O)2 5 39 5.639 89.78 6 91.34 Ginderow 1983 l Chains [(UO2)(SeO4)(H 14.65 10.7 12.66 119.9 No No Infinite Se 2O)2](H2O)2 3 99 4 90 5 90 Serezhkin 1981 data data Chains Ca[(UO2)(SeO3) 5.550 6.64 11.01 104.05 93.34 soluti 151- Infinite

251 Se 2] 2 15 3 5 2 110.589 Almond 2002 on 300 Chains Sr[(UO2)(SeO3) 5.672 6.76 11.26 104.69 93.70 soluti Infinite Se 2] 2 27 22 8 8 109.489 Almond 2004 on 300+ Chains Sr[(UO2)(SeO3) 7.054 7.46 10.04 106.99 108.0 soluti 151- Infinite Se 2]dot2H2O 5 56 84 5 28 98.875 Almond 2002 on 300 Chains Cs2[(UO2)(SeO 14.36 11.6 soluti Se 4)2H2O]H2O 7 82 7.826 90 90 90 Mikhailov 2001 on RT Sheets - V Tl2[(UO2)(MoO 10.97 14.0 14.04 Krivoviche solid 501- Se 4)2] 7 04 1 90 90 90 v 2005 state 1000 Sheets - V K[(UO2)(HSeO3 8.416 10.1 9.691 97.55 soluti 151- Se )(SeO3)] 4 435 3 90 6 90 Almond 2002 on 300 Sheets - V Rb[(UO2)(HSeO 8.416 10.2 9.854 96.82 soluti 151- Se 3)(SeO3)] 7 581 2 90 5 90 Almond 2002 on 300 Sheets - V Cs[(UO2)(HSeO 13.85 10.6 12.59 101.0 soluti 151- Se 3)(SeO3)] 29 153 21 90 94 90 Almond 2002 on 300 Sheets - V Tl[(UO2)(HSeO 10.3 97.26 soluti 151- Se 3)(SeO3)] 8.364 46 9.834 90 9 90 Almond 2002 on 300 Sheets - V

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe (NH4)2UO2(Se 10.3 13.82 Koskenlinn soluti Se O3)2(H2O)0.5 7.193 68 3 90 91.47 90 a 1997 on 31-150 Sheets - V (NH4)[(UO2)(H 10.3 Koskenlinn soluti Se SeO3)(SeO3)] 8.348 26 9.929 90 97.06 90 a 1996 on 31-150 Sheets - V Ag2(UO2)(SeO3 5.855 6.50 21.16 96.79 soluti 151- Se )2 5 51 4 90 6 90 Almond 2002 on 300 Sheets - V Zn2[(UO2)3(Se 18.42 19.9 20.69 Krivoviche soluti Se O4)5](H2O)17 88 793 01 90 90 90 v 2005 on RT Sheets - V Pb(UO2)(SeO3) 11.99 5.78 11.25 soluti Se 2 11 14 25 90 90 90 Almond 2002 on 31-150 Sheets - V Ba[(UO2)(SeO3 7.306 8.12 13.65 100.3 soluti 151- Se )2] 7 39 1 90 75 90 Almond 2002 on 300 Sheets - V NH4[(UO2)F(Se 13.4 13.56 soluti Se O4)](H2O) 8.45 83 9 90 90 90 Blatov 1989 on RT Sheets - V

252 Marthozi Cu[(UO2)3(SeO 6.987 16.4 17.22 natura Sheets - Se te 3)2O2](H2O)8 9 537 29 90 90 90 Cooper 2001 l TSPH Guillemi Ba[(UO2)3(SeO 7.29 16.88 natura Sheets - Se nite 3)2O2](H2O)3 7.084 3 1 90 90 90 Cooper 1995 l TSPH Na(H3O)[(UO2) 3(SeO3)2O2](H 6.980 7.64 17.24 natura Sheets - Se Larisaite 2O)4 6 6 9 90 90 90.039 Chukanov 2004 l TSPH Sr[(UO2)3(SeO3 17.01 7.06 7.108 100.5 soluti Sheets - Se )2O2](H2O)4 4 37 4 90 44 90 Almond 2004 on 300+ TSPH 9.27 4.254 solid Se [(UO2)(SeO3)] 5.408 8 5 90 93.45 90 Loopstra 1978 state 0-500 Sheets - H 5.52 13.31 103.7 Brandenbu soluti 151- Infinite Se α-(UO2)(SeO4) 6.909 5 8 90 9 90 rg 1978 on 300 Frameworks alpha- Mg2[(UO2)3(Se 19.54 10.4 91.35 Krivoviche soluti Infinite Se O4)5](H2O)16 4 783 18.02 90 2 90 v 2004 on RT Frameworks

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Beta- Mg2[(UO2)3(Se 10.38 22.2 33.73 Krivoviche soluti Infinite Se O4)5](H2O)16 07 341 9 90 90 90 v 2004 on RT Frameworks Mg[UO2)(SeO4) 8.466 11.6 13.16 90.95 Krivoviche soluti Se 2(H2O)](H2O)4 6 306 69 90 9 90 v 2005 on RT Sheets Zn[UO2)(SeO4) 8.449 11.5 92.38 Krivoviche soluti Se 2(H2O)](H2O)4 2 86 13.24 90 2 90 v 2005 on RT Sheets (H3O)6[(UO2)5 (SeO4)8(H2O)5 13.83 13.4 108.0 Krivoviche soluti Se ](H2O)5 5 374 14.31 90 04 90 v 2005 on RT Sheets (H3O)2[(UO2)2 (SeO4)3(H2O)2 11.94 13.6 13.72 109.4 Krivoviche soluti Se ](H2O)3.5 02 452 71 90 36 90 v 2005 on RT Sheets Co2[(UO2)3(Se 10.45 11.0 17.89 Krivoviche soluti

253 Se O4)5](H2O)16 8 32 3 89.451 90.28 61.761 v 2005 on RT Sheets Zn2[(UO2)3(Se 10.43 11.0 17.89 Krivoviche soluti Se O4)5](H2O)16 8 63 5 89.19 89.85 61.72 v 2005 on RT Sheets K5[(UO2)3(SeO 4)5](NO3)(H2O 11.20 18.2 32.36 Krivoviche soluti Infinite Se )3.5 48 132 4 90 90 90 v 2005 on 31-150 Frameworks Rb2[(UO2)(SeO 4)2(H2O)](H2O 13.67 11.8 7.639 Krivoviche soluti Se ) 7 707 7 90 90 90 v 2005 on RT Sheets Rb2[(UO2)2(Se O4)3(H2O)2](H 8.426 11.8 13.32 102.61 107.2 Krivoviche soluti Se 2O)4 1 636 79 2 5 102.51 v 2005 on RT Sheets Na2[(UO2)2(Se O4)3(H2O)2](H 19.73 10.8 21.35 103.4 soluti Infinite Se 2O)6.5 66 206 77 90 31 90 Baeva 2006 on RT Frameworks Na6[(UO2)3(Se O4)2O(OH)3]2( 14.22 18.3 16.54 soluti Infinite Se H2O)10 25 601 06 90 90 90 Baeva 2006 on RT Frameworks

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Na[(UO2)(SeO3 )(HSeO3)](H2O 8.803 10.4 13.13 105.0 soluti Infinite Se )4 2 61 12 90 54 90 Marukhnov 2008 on RT Frameworks (H3O)2(UO2)(S 7.53 21.38 101.4 Krivoviche soluti Se eO4)2(H2O)2 7.867 57 6 90 84 90 v 2008 on RT Sheets (H3O)2(UO2)(S 14.03 11.6 8.214 Krivoviche soluti Se eO4)2(H2O)3 28 412 6 90 90 90 v 2008 on RT Sheets (UO2)(SeO4)[(D 2O)1.65(H2O)0. 8.28 11.66 92.31 soluti Infinite Se 35) 6.974 9 4 90 9 90 Marukhnov 2008 on 31-150 Frameworks Cs[(UO2)(SeO3) (HSeO3)](H2O) 10.4 13.23 105.1 soluti 151- Se 3 8.673 52 5 90 47 90 Burns 2009 on 300 Sheets Na3(H3O)(UO2( 9.60 11.74 soluti Infinite

254 Se SeO3)2)2(H2O) 9.543 2 2 66.693 84.1 63.686 Serezhkina 2009 on 31-150 Chains 11.5 No No Se U O2 Se2 O5 9.405 74 6.698 93.01 93.66 109.69 1985 data data No data (N H4)4 ((U O2) (Se O4) (C2 O4) 18.98 8.34 14.99 No No Se (H2 O))2 (H2 O) 2 3 4 90 93.12 90 1996 data data No data Rb (U O2 (Se O4) (O H) (H2 8.08 11.79 107.2 No No Se O)) 8.273 5 1 90 2 90 2001 data data No data (H3 O)3 ((U O2)3 O (O H)3 9.56 22.70 No No Se (Se O4)2) 9.567 7 3 90 90 120 2003 data data No data Rb4 ((U O2)3 (Se O4)5 (H2 11.37 15.0 19.20 No No Se O)) 61 69 89 90 90 90 2005 data data No data ((H5 O2) (H3 O) (H2 O)) ((U O2) 8.310 11.0 13.22 103.8 No No Se (Se O4)2) 5 799 7 90 8 90 2008 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe (H3 O) (U O2 (Se O4) (Se O2 8.668 10.6 97.88 No No Se (O H))) 2 545 9.846 90 1 90 2008 data data No data α- uranoph Ca[(UO2)(SiO3 15.90 7.00 natura Si ane OH)]2(H2O)5 9 2 6.665 90 97.27 90 Ginderow 1988 l Sheets - TSP (K0.56Na).42)[( Boltwoo UO2)(SiO3OH)] 7.077 7.05 6.647 104.9 natura Si dite (H2O)1.5 2 97 9 90 82 90 Burns 1998 l Sheets - TSP Cs[(UO2)(SiO3O 7.475 7.08 6.665 104.1 soluti 151- Si H)]2 6 67 7 90 55 90 Burns 1999 on 300 Sheets - TSP Cuproskl odowskit Cu[(UO2)(SiO3 9.26 Rosenzwei natura Si e OH)]2(H2O)6 7.052 7 6.655 109.23 89.84 110.01 g 1975 l Sheets - TSP

255 Sklodow Mg[(UO2)(SiO3 17.38 7.04 Rosenzwei natura Si skite OH)]2(H2O)6 2 7 6.61 90 105.9 90 g 1977 l Sheets - TSP

Pb[(UO2)(SiO4) 6.93 13.25 104.2 Rosenzwei natura Si Kasolite ](H2O) 6.704 2 2 90 2 90 g 1977 l Sheets - TSP Co[(UO2)(SiO3 7.049 17.5 12.73 natura Si Oursinite OH)]2(H2O)6 4 5 4 90 90 90 Kubatko 2006 l Sheets - TSP β- uranoph Ca[(UO2)(SiO3 13.96 15.4 Viswanatha natura Si ane OH)]2(H2O)5 6 43 6.632 90 91.38 90 n 1986 l Sheets - TSP Ca[(UO2)2Si5O Haiweeit 12(OH)2](H2O) 17.9 18.34 natura Si e 3 7.125 37 2 90 90 90 Burns 2001 l Sheets - Misc Kna3(UO2)2(Si 12.78 13.6 8.251 119.2 solid Infinite Si 4O10)2(H2O)4 06 215 5 90 26 90 Burns 2000 state 1000+ Frameworks Na4(UO2)2(Si4 12.78 13.6 8.251 119.2 soluti 151- Infinite Si O10)2(H2O)4 06 215 5 90 26 90 Li 2001 on 300 Frameworks (UO2)2(SiO4)(H 11.2 18.66 natura Infinite Si Soddyite 2O)2 8.334 12 8 90 90 90 Demartin 1992 l Frameworks

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe K1.26Ba0.25Ca 0.12[(UO2)2(Si 14.24 14.2 35.86 natura Infinite Si Weeksite 5O13)]H2O 8 09 9 90 90 90 Jackson 2001 l Frameworks Na2(UO2)(SiO4 12.71 12.7 13.37 soluti Infinite Si ) 8 18 6 90 90 90 Shashkin 1974 on 300+ Frameworks RbNa(UO2)(Si2 7.366 7.86 8.176 75.01 soluti 151- Infinite Si O6)dotH2O 8 91 6 78.024 3 83.741 Wang 2002 on 300 Frameworks K5(UO2)2[Si4O 13.12 12.2 22.23 soluti Infinite Si 12(OH)] 74 635 28 90 90 90 Chen 2005 on 300+ Frameworks (K3Cs4F)[(UO2) 7.809 22.2 14.08 solid 501- Infinite Si 3(Si2O7)2] 5 819 61 90 90 90 Lee 2009 state 1000 Frameworks (NaRb6F)[(UO2 11.14 13.5 7.886 solid 501- Infinite Si )3(Si2O7)2] 29 151 8 90 90 90 Lee 2009 state 1000 Frameworks Na2 (U O2)2 (Si 6.97 No No

256 Si O4) F2 6.975 5 18.31 90 90 90 1999 data data No data Na14 (Na2 (U O2)2 (Si W9 O34)2) (H2 16.57 14.6 21.25 111.6 No No Si O)38 19 189 28 90 77 90 2002 data data No data Li18 Na4 ((Na (H2 O))4 (U O2)4 (O H)2 (Si W10 O36)4) 26.52 26.5 15.04 No No Si (H2 O)58.92 85 285 63 90 90 90 2002 data data No data Na14 K8 ((K (H2 O))4 (U O2)4 (O H)2 (Si W10 O36)4) 31.6 58.01 No No Si (H2 O)62 24.18 96 2 90 90 90 2002 data data No data Rb2 (U O2) (Si2 14.62 15.1 16.64 No No Si O6) (H2 O)0.5 7 447 46 90 90 90 2003 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Rb2 (U O2) (Si2 7.698 20.9 97.91 No No Si O6) (H2 O) 9 74 12.05 90 9 90 2003 data data No data Cs2 (U O2) (Si2 15.04 15.4 16.73 No No Si O6) (H2 O)0.5 72 265 15 90 90 90 2003 data data No data Cs2 (U O2) Si2 15.13 15.2 16.40 No No Si O6 72 949 1 90 90 90 2005 data data No data 6.012 6.21 8.613 90.23 solid 501- Isolated Sr Sr3[UO6] 6 38 9 90 9 90 Ijdo 1993 state 1000 Polyhedra 8.104 5.66 11.91 108.9 No No Infinite Sr Sr2[(UO2)O3] 3 14 85 90 85 90 Loopstra 1969 data data Chains 5.489 7.97 8.129 No No Sr Sr[(UO2)O2] 6 7 7 90 90 90 Loopstra 1969 data data Sheets - V Sr1.27[(UO2)3O 3.54(OH)1.46]( soluti 151-

257 Sr H2O)3 7.02 7.02 6.992 90 90 120 Burns 2002 on 300 Sheets - TP [Sr3(UO2)11O1 28.50 8.38 6.733 solid 501- Sr 4] 8 06 3 90 90 90 Cordfunke 1991 state 1000 Sheets - TSP Sr2.82(H2O)2[( UO2)4O3.82(O 12.31 12.9 8.405 soluti 151- Sr H)3.18]2 43 609 3 90 90 90 Burns 2000 on 300 Sheets - TSP 7.98 No No Sr α-Sr[(UO2)O2] 5.493 3 8.128 90 90 90 Fujino 1977 data data Sheets - H 5.489 7.97 8.129 No No Sr γ-Sr[(UO2)O2] 6 7 7 90 90 90 Fujino 1977 data data Sheets - H Sr5(UO2)20(UO 6)2O16(OH)6(H 11.66 21.0 14.37 soluti 151- Infinite Sr 2O)6 77 65 25 90 90 90 Kubatko 2006 on 300 Frameworks 10.78 10.7 10.78 solid Infinite Ta Cs(TaUO6) 52 852 52 90 90 90 Knyazev 2009 state 1000+ Frameworks 6.26 No No Ta U2 Ta6 O19 6.266 6 19.86 90 90 120 2000 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe β- Tl2[UO2(TeO3) 5.476 8.23 20.84 92.32 soluti 151- Infinite Te 2] 6 48 9 90 9 90 Almond 2002 on 300 Chains Sr3[(UO2)(TeO 5.65 13.10 94.41 soluti 151- Infinite Te 3)2](TeO3)2 20.54 47 09 90 7 90 Almond 2002 on 300 Chains Schmitte 10.16 5.36 solid 501- Te rite [(UO2)(TeO3)] 1 3 7.862 90 90 90 Meunier 1973 state 1000 Sheets - TSP K[UO2Te2O5(O 7.999 8.74 11.44 soluti 151- Te H)] 3 16 13 90 90 90 Almond 2002 on 300 Sheets - Misc Tl3{(UO2)2[Te2 O5(OH)](Te2O6 10.06 23.0 7.938 soluti 151- Te )}dot2H2O 23 24 9 90 90 90 Almond 2002 on 300 Sheets - Misc Pb2(UO2)(TeO3 11.60 13.3 Brandstatte No No Infinite Te )3 5 89 6.981 90 91.23 90 r 1981 data data Frameworks

258 Cliffordit 11.3 Brandstatte soluti Infinite Te e (UO2)(Te3O7) 11.37 7 11.37 90 90 90 r 1981 on 300+ Frameworks Na8[(UO2)6(Te 16.89 16.8 16.89 soluti 151- Infinite Te O3)10] 69 969 69 90 90 90 Almond 2002 on 300 Frameworks K2[(UO2)3(TeO 6.798 7.01 7.896 101.85 102.9 solid 501- Te 3)2O2] 9 23 5 2 74 100.081 Woodward 2004 state 1000 Sheets Rb2[(UO2)3(Te 7.010 7.07 8.084 105.50 101.7 solid 501- Te O3)2O2] 1 42 8 9 6 99.456 Woodward 2004 state 1000 Sheets Cs2[(UO2)3(Te 7.000 7.51 8.432 100.5 solid 501- Te O3)2O2] 7 95 7 109.3 7 99.5 Woodward 2004 state 1000 Sheets K4[(UO2)5(TeO 6.851 7.10 11.31 93.59 solid 501- Te 3)2O5] 4 64 35 99.642 1 100.506 Woodward 2005 state 1000 Sheets [(UO2)TiNb2O8 12.6 No No Ti ] 7.28 2 16.02 90 90 90 Chevalier 1969 data data Sheets - H 6.446 8.59 10.25 75.93 soluti Ti Ba[(UO2)TiO4)] 3 99 32 90 6 90 Wallwork 2006 on 300+ Sheets

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe (U O2)1.77 Ti Ca0.25 O3.61 (O 10.82 10.8 No No Ti H)0.67 (H2 O)3 4 24 7.549 90 90 120 2005 data data No data Tl2(UO2)[(UO2) 12.97 15.1 9.338 132.3 soluti 151- Infinite Tl (PO4)]4(H2O)2 98 639 4 90 1 90 Locock 2004 on 300 Frameworks Ba0.96Pb0.04[( Francevil UO2)2(V2O8)]( 10.41 16.76 natura V lite H2O)5 9 8.51 3 90 90 90 Mereiter 1986 l Sheets - TSP Pb[(UO2)2(V2O 10.41 8.49 16.40 natura V Curienite 8)](H2O)5 9 4 5 90 90 90 Borene 1971 l Sheets - TSP K2[(UO2)2(V2O 103.8 solid V 8)] 10.47 8.41 6.59 90 3 90 Appleman 1965 state 1000+ Sheets - TSP Cu2[(UO2)2(V2 Sengierit O8)](OH)2(H2O 10.59 8.09 10.08 103.4 natura

259 V e )6 9 3 5 90 2 90 Piret 1980 l Sheets - TSP Ni[(UO2)2(V2O natura V 8)](H2O)4 10.6 8.25 15.12 90 90 90 Borene 1970 l Sheets - TSP Cs2[(UO2)2(V2 10.52 8.43 106.0 soluti V O8)] 1 69 7.308 90 8 90 Dickens 1992 on 31-150 Sheets - TSP K6(UO2)5(VO4) 24.7 solid 501- V 2O5 6.856 97 7.135 90 98.79 90 Dion 2000 state 1000 Sheets - TSP Na6(UO2)5(VO 12.58 24.3 100.6 solid 501- V 4)2O5 4 6 7.05 90 1 90 Dion 2000 state 1000 Sheets - TSP α- 24.88 7.09 14.37 103.9 solid 501- V Rb6U5V2O23 7 9 6 90 2 90 Obbade 2003 state 1000 Sheets - TSP β- 7.163 14.0 24.96 solid 501- V Rb6U5V2O23 5 79 5 90 90.23 90 Obbade 2003 state 1000 Sheets - TSP 11.90 6.82 12.09 106.9 solid 501- V Cs[Uv3O11] 4 1 5 90 89 90 Duribreux 1999 state 1000 Sheets - H Cs4[(UO2)2(V2 8.482 13.4 7.136 solid 501- V O7)O2] 8 26 6 90 90 90 Obbade 2004 state 1000 Sheets - Misc

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe (UO2)[(UO2)(V 17.97 13.5 soluti 151- Infinite V O4)]2(H2O)5 8 61 7.163 90 90 90 Saadi 2000 on 300 Frameworks 5.649 13.1 7.284 119.7 solid 501- Infinite V (UO2)2V2O7 2 841 4 90 45 90 Tancret 1995 state 1000 Frameworks Na(UO2)4(VO4) 7.226 7.22 34.07 solid 501- Infinite V 3 7 67 9 90 90 90 Obbade 2004 state 1000 Frameworks 6.499 8.38 10.42 104.7 solid 501- V Ba(VUO6)2 2 03 35 90 49 90 Alekseev 2004 state 1000 Sheets 6.921 9.65 11.78 solid 501- Infinite V Pb(UO2)(V2O7) 2 23 81 90 91.74 90 Obbade 2004 state 1000 Frameworks Cs2[(UO2)(VO2 )2(PO4)2](H2O 20.71 6.85 10.54 soluti 151- Infinite V )0.59 16 64 97 90 90 90 Shvareva 2005 on 300 Frameworks (NH4)2[(UO2)2 8.38 10.47 106.0 soluti 151-

260 V V2O8] 6.894 4 3 90 66 90 Rivenet 2007 on 300 Sheets Li2(UO2)3(VO4 7.330 7.33 24.65 solid 501- Infinite V )2O 3 03 3 90 90 90 Obbade 2007 state 1000 Frameworks K3.48[(UO2)H1. 52(VO)4(PO4)5 7.380 9.15 17.08 soluti 151- V ] 3 77 98 90 90 90 Shvareva 2007 on 300 Sheets Ag3(UO2)7(VO 7.237 7.23 14.79 solid 501- Infinite V 4)5O 3 73 73 90 90 90 Obbade 2009 state 1000 Frameworks Li3(UO2)7(VO4 7.279 7.27 14.51 solid 501- Infinite V )5O 4 94 4 90 90 90 Obbade 2009 state 1000 Frameworks Cs7 (U O2)8 (V 21.45 11.7 No No V O4)2 Cl O8 8 73 7.495 90 90 90 2003 data data No data Rb7 (U O2)8 (V 21.42 11.8 14.20 No No V O4)2 Cl O8 7 14 3 90 90 90 2003 data data No data K2[(UO2)2(VO) 2(IO6)2O]dotH 16.7 4.977 soluti 151- Infinite V/I 2O 9.984 63 3 90 90 90 Sykora 2003 on 300 Frameworks

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe K2(UO2)2(WO5 28.7 102.1 solid 501- W )O 8.083 24 9.012 90 4 90 Obbade 2003 state 1000 Sheets - TSP Rb2(UO2)2(WO 28.7 104.5 solid 501- W 5)O 8.234 4 9.378 90 9 90 Obbade 2003 state 1000 Sheets - TSP K2[(UO2)(W2O 7.588 8.61 13.94 solid 501- W 8)] 4 57 6 90 90 90 Obbade 2003 state 1000 Sheets - H Na2[(UO2)W2O 6.648 7.53 8.486 Krivoviche solid 501- W 8] 4 08 9 89.952 86.19 73.299 v 2003 state 1000 Sheets - H α- Ag2[(UO2)W2 8.426 7.48 12.92 95.44 Krivoviche solid 501- W O8] 3 97 7 90 3 90 v 2003 state 1000 Sheets - H β- Ag2[(UO2)W2 8.641 7.56 12.45 Krivoviche solid 501- W O8] 5 1 13 90 90 90 v 2003 state 1000 Sheets - H

261 Cs6(UO2)4(W5 O21)(OH)2(H2 15.95 15.9 14.21 soluti 151-

W O)2 93 593 49 90 90 90 Sykora 2004 on 300 Sheets - Misc Li2(UO2)(WO4) 7.937 12.7 7.424 solid 501- Infinite W 2 2 86 9 90 90 90 Obbade 2004 state 1000 Frameworks Li2(UO2)4(WO 14.01 6.31 22.29 solid 501- Infinite W 4)4O 9 16 6 90 98.86 90 Obbade 2004 state 1000 Frameworks Cs2(UO2)2(WO 28.9 107.7 solid 501- W 6) 8.611 1 9.499 90 3 90 Alekseev 2006 state 1000 Sheets Na2Li8[(UO2)1 6.945 11.2 12.05 106.2 solid 501- Infinite W 1O12(WO5)2] 8 07 4 99.525 1 90.223 Alekseev 2006 state 1000 Frameworks Rb8[(UO2)4(W 11.09 13.1 25.01 90.03 solid 501- Infinite W O4)4(WO5)2] 8 61 7 90 3 90 Alekseev 2006 state 1000 Frameworks Cs8[(UO2)4(W 11.25 13.8 25.73 89.99 solid 501- Infinite W O4)4(WO5)2] 2 15 6 90 8 90 Alekseev 2006 state 1000 Frameworks Rb6[(UO2)2O( 10.18 13.1 18.82 96.57 solid 501- Infinite W WO4)4] 8 1 2 97.855 3 103.894 Alekseev 2006 state 1000 Frameworks

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe Li4[(UO2)2(W2 7.382 14.0 10.18 solid 501- W O10)] 3 498 87 90 90 90 Alekseev 2007 state 1000 Sheets Na10 (U O2)8 24.35 23.5 6.806 No No W (W5 O20) O8 9 06 8 90 94.85 90 2003 data data No data 5.81 8.200 89.95 solid 501- Infinite Zn Sr2ZnUO6 5.832 19 4 90 8 90 Pinacca 2007 state 1000 Frameworks 6.72 solid Infinite Li4[(UO2)O3] 6.721 1 4.451 90 90 90 Reshetov 1966 state 1000+ Chains [(UO2)(O2)(H2 14.06 6.72 123.3 natura Infinite Studtite O)2](H2O)2 8 1 8.428 90 56 90 Burns 2003 l Chains 18.16 Zachariase No No K3(UO2)F5 9.16 9.16 7 90 90 90 n 1954 data data No data 5.52 112.7 soluti γ-[(UO2)(OH)2] 5.56 2 6.416 90 1 90 Siegel 1972 on 31-150 Sheets - V

262 5.643 6.28 9.937 No No β-[(UO2)(OH)2] 8 67 2 90 90 90 Taylor 1972 data data Sheets - V 11.9 solid 501- α-U3O8 6.716 6 4.147 90 90 90 Loopstra 1977 state 1000 Sheets - TP Metasch [(UO2)4O(OH)6 14.68 13.9 16.70 soluti oepite ](H2O)5 61 799 63 90 90 90 Weller 2000 on RT Sheets - TP Schoepit [(UO2)8O2(OH) 14.33 16.8 14.73 natura e 12](H2O)12 7 13 1 90 90 90 Finch 1996 l Sheets - TP 7.41 soluti [H2(UO2)3O4] 6.802 7 5.556 108.5 125.5 88.2 Siegel 1972 on 300+ Sheets - TSP 11.4 No No β-U3O8 7.069 45 8.303 90 90 90 Loopstra 1970 data data Sheets - TSP [U24+(UO2)4O Ianthinit 6(OH)4(H2O)4] 11.4 natura e (H2O)5 7.178 73 30.39 90 90 90 Burns 1997 l Sheets - TSP 6.95 No No CoUO4 6.497 2 6.497 90 90 90 Bertaut 1962 data data No data

TABLE C.1 (CONTINUED)

Syn_T Syn_Te Structure_Ty Name Formula a b c alpha beta gamma Author Year ype mp pe No No α-UO3 3.961 6.86 4.166 90 90 90 Loopstra 1966 data data Sheets - H 5.643 6.28 9.937 No No α-[(UO2)(OH)2] 8 67 2 90 90 90 Taylor 1971 data data Sheets - H 19.9 solid 501- Infinite γ-UO3 9.787 32 9.705 90 90 90 Loopstra 1977 state 1000 Frameworks 14.3 solid Infinite β-UO3 10.34 3 3.91 90 99.03 90 Debets 1966 state 0-500 Frameworks 4.16 soluti 151- Infinite δ-UO3 4.165 5 4.165 90 90 90 Weller 1988 on 300 Frameworks Na4[(UO2)(O2) 17.2 14.18 No No 3](H2O)9 6.413 92 6 90 98.52 90 Alcock 1968 data data No data 4.74 No No Rh2UO6 4.744 4 9.36 90 90 90 Omaly 1972 data data No data

263 [(UO2)4O(OH)6 14.68 14.0 16.71 Klingensmi natura ](H2O)5 01 287 96 90 90 90 th 2007 l Sheets [U5+(H2O)2(UO 2)2O4)(OH)](H 7.175 soluti 2O)4 7 11.4 15.31 90 90 90 Belai 2008 on 31-150 Sheets (NH4)2[(UO2)2 No No No No No No (C2O4)3] data data data No data data No data Alcock 1973 data data No data 7.29 18.91 No No Li2 (U O2)3 O4 6.818 8 4 90 90 121.58 Spitsyn 1982 data data No data

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