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Zintl and Intermetallic Phases Grown from Calcium/Lithium Flux Trevor Blankenship

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Zintl and Intermetallic Phases Grown from Calcium/Lithium Flux Trevor Blankenship Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2014 Zintl and Intermetallic Phases Grown from Calcium/Lithium Flux Trevor Blankenship Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] FLORIDA STATE UNIVERSITY COLLEGE OF ARTS AND SCIENCES ZINTL AND INTERMETALLIC PHASES GROWN FROM CALCIUM/LITHIUM FLUX By TREVOR BLANKENSHIP A Dissertation submitted to the Department of Chemistry and Biochemistry in partial fulfillment of the requirements for the degree of Doctor of Philosophy Degree Awarded: Fall Semester, 2014 Trevor Blankenship defended this dissertation on September 25, 2014. The members of the supervisory committee were: Susan Latturner Professor Directing Dissertation Bruce Locke University Representative Albert Stiegman Committee Member Igor Alabugin Committee Member The Graduate School has verified and approved the above-named committee members, and certifies that the dissertation has been approved in accordance with university requirements. ii ACKNOWLEDGEMENTS I would like to foremost give my deep appreciation to Dr. Susan Latturner whose advice and guidance were critical in completion of my degree. She has been committed to her mentorship role and my development as a scientist. The NMR studies were possible due to the work of Dr. Chen who enthusiastically tackled some difficult problems. Dr. Clark has been gracious in giving time and knowledge to assist with solving crystal structures. I would also like to thank the past members of the Latturner group who have assisted me in matters great and small over the years. In particular, Dr. Gina Canfield, Dr. Josiah Matthieu, and Dr. Patricia Tucker have all greatly helped. This work was built on the work of David Lang who gave a great starting point and introduced me to the basics of flux synthesis. Finally, I would like to thank my parents who have given their full support in everything I have wished to do. Unfortunately my father was not able to see me graduate; this work is dedicated to his memory. iii TABLE OF CONTENTS List of Tables ................................................................................................................................. vi List of Figures ............................................................................................................................... vii Abstract ............................................................................................................................................x 1. INTRODUCTION .......................................................................................................................1 1.1 Metal Flux Synthesis......................................................................................................1 1.2 Intermetallics..................................................................................................................2 1.3 Zintl Phases ....................................................................................................................2 2. EXPERIMENTAL TECHNIQUES .............................................................................................4 2.1 Synthesis in the Ca/Li Flux ............................................................................................4 2.2 SEM-EDS ......................................................................................................................5 2.3 X-ray Photoelectron Spectroscopy ................................................................................7 2.4 X-Ray Diffraction ..........................................................................................................7 2.5 Solid-State Nuclear Magnetic Resonance ......................................................................8 2.6 Band Structure Calculation ............................................................................................9 3. COMPLEX CARBIDE PHASES CA11E3C8 (E = Sn,Pb) GROWN FROM THE Ca/Li FLUX ............................................................................................................................................10 3.1 Introduction ..................................................................................................................10 3.2 Experimental ................................................................................................................11 3.3 Results and Discussion ................................................................................................15 3.4 Conclusions ..................................................................................................................23 4. LICA3AS2H AND CA14AS6X7 (X = C, H, N): TWO NEW ARSENIDE HYDRIDE SALTS GROWN FROM Ca/Li METAL FLUX ........................................................................................24 4.1 Introduction ..................................................................................................................24 4.2 Experimental Section ...................................................................................................25 4.3 Results and Discussion ................................................................................................30 4.4 Conclusions ..................................................................................................................38 5. Ca54In13B4–xH23+x: A COMPLEX METAL SUBHYDRIDE FEATURING IONIC AND METALLIC REGIONS ................................................................................................................39 5.1 Introduction ..................................................................................................................39 5.2 Experimental ................................................................................................................40 5.3 Results and Discussion ................................................................................................46 5.4 Conclusions ..................................................................................................................56 6. ALKALINE EARTH INDIUM ALLENYLIDES SYNTHESIZED IN AE/Li FLUX iv (AE = Ca, Ba) ................................................................................................................................57 6.1 Introduction ..................................................................................................................57 6.2 Experimental Procedure ...............................................................................................58 6.3 Results and Discussion ................................................................................................62 6.4 Conclusions ..................................................................................................................73 7. Future Work ...............................................................................................................................74 7.1 Introduction ..................................................................................................................74 7.2 Synthesis ......................................................................................................................74 7.3 Structure of Ca31H21Al2................................................................................................75 7.4 Structure of Ca4Al2N5 ..................................................................................................78 7.5 Structure of Ca24Al9(C1-xHx)N2H16 ..............................................................................79 8. CONCLUSIONS........................................................................................................................83 REFERENCES ..............................................................................................................................84 BIOGRAPHICAL SKETCH .........................................................................................................94 v LIST OF TABLES Table 3.1 Crystallographic data and collection parameters for Ca11E3C8 phases. ................ 12 Table 3.2 Atomic coordinates and isotropic thermal parameters of Ca11Sn3C8. .................. 13 Table 3.3 Atomic coordinates and isotropic thermal parameters of Ca11Pb3C8.................... 14 Table 3.4 Bond lengths of interest in Ca11Tt3C8 phases, in angstroms. ................................ 20 Table 4.1 Crystallographic data and collection parameters for title phases. ......................... 28 Table 4.2 Atomic positions and site occupancies for Ca14As6C0.46N1.155H5.045..................... 29 Table 4.3 Bond lengths of interest in arsenide hydride phases, in angstroms. ..................... 31 Table 5.1 Crystallographic data and collection parameters for two samples of Ca53In13B4H23 ........................................................................................................ 43 Table 5.2 Atom positions and isotropic thermal parameters for Ca53In13B4H23 ................... 44 Table 5.3 Atom positions and isotropic thermal parameters for the second crystal of Ca53In13B4H23 ........................................................................................................ 44 Table 6.1 Crystallographic data collection parameters for the title phases. ......................... 61 Table 6.2 Atomic coordinates and isotropic thermal parameters for the title phases. .......... 62 Table 6.3 Bond lengths (Å) in title phases. ..........................................................................
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