Computational and Experimental Studies of Solids in the Ammonia
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Evasive Ice X and Heavy Fermion Ice XII: Facts and Fiction About High
Physica B 265 (1999) 113—120 Evasive ice X and heavy fermion ice XII: facts and fiction about high-pressure ices W.B. Holzapfel* Fachbereich Physik, Universita( t-GH Paderborn, D-33095 Paderborn, Germany Abstract Recent theoretical and experimental results on the structure and dynamics of ice in wide regions of pressure and temperature are compared with earlier models and predictions to illustrate the evasive nature of ice X, which was originally introduced as completely ordered form of ice with short single centred hydrogen bonds isostructural CuO. Due to the lack of experimental information on the proton ordering in the pressure and temperature region for the possible occurrence of ice X, effects of thermal and quantum delocalization are discussed with respect to the shape of the phase diagram and other structural models consistent with present optical and X-ray data for this region. Theoretical evidences for an additional orthorhombic modification (ice XI) at higher pressures are confronted with various reasons supporting a delocalization of the protons in the form of a heavy fermion system with very unique physical properties characterizing this fictitious new phase of ice XII. ( 1999 Elsevier Science B.V. All rights reserved. Keywords: Ices; Hydrogen bonds; Phase diagram; Equation of states 1. Introduction tunnelling [2]. Detailed Raman studies on HO and DO ice VIII to pressures in the range of The first in situ X-ray studies on HO and DO 50 GPa [3] revealed the expected softening in the ice VII under pressures up to 20 GPa [1] together molecular stretching modes and led to the deter- with a simple twin Morse potential (TMP) model mination of a critical O—H—O bond length of " for protons or deuterons in hydrogen bonds [2] R# 232 pm, where the central barrier of the effec- allowed almost 26 years ago first speculations tive double-well potential should disappear [4]. -
11Th International Conference on the Physics and Chemistry of Ice, PCI
11th International Conference on the Physics and Chemistry of Ice (PCI-2006) Bremerhaven, Germany, 23-28 July 2006 Abstracts _______________________________________________ Edited by Frank Wilhelms and Werner F. Kuhs Ber. Polarforsch. Meeresforsch. 549 (2007) ISSN 1618-3193 Frank Wilhelms, Alfred-Wegener-Institut für Polar- und Meeresforschung, Columbusstrasse, D-27568 Bremerhaven, Germany Werner F. Kuhs, Universität Göttingen, GZG, Abt. Kristallographie Goldschmidtstr. 1, D-37077 Göttingen, Germany Preface The 11th International Conference on the Physics and Chemistry of Ice (PCI- 2006) took place in Bremerhaven, Germany, 23-28 July 2006. It was jointly organized by the University of Göttingen and the Alfred-Wegener-Institute (AWI), the main German institution for polar research. The attendance was higher than ever with 157 scientists from 20 nations highlighting the ever increasing interest in the various frozen forms of water. As the preceding conferences PCI-2006 was organized under the auspices of an International Scientific Committee. This committee was led for many years by John W. Glen and is chaired since 2002 by Stephen H. Kirby. Professor John W. Glen was honoured during PCI-2006 for his seminal contributions to the field of ice physics and his four decades of dedicated leadership of the International Conferences on the Physics and Chemistry of Ice. The members of the International Scientific Committee preparing PCI-2006 were J.Paul Devlin, John W. Glen, Takeo Hondoh, Stephen H. Kirby, Werner F. Kuhs, Norikazu Maeno, Victor F. Petrenko, Patricia L.M. Plummer, and John S. Tse; the final program was the responsibility of Werner F. Kuhs. The oral presentations were given in the premises of the Deutsches Schiffahrtsmuseum (DSM) a few meters away from the Alfred-Wegener-Institute. -
Properties of Ices at 0 K: a Test of Water Models J
THE JOURNAL OF CHEMICAL PHYSICS 127, 154518 ͑2007͒ Properties of ices at 0 K: A test of water models J. L. Aragones, E. G. Noya, J. L. F. Abascal, and C. Vega Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense, 28040 Madrid, Spain ͑Received 9 July 2007; accepted 27 July 2007; published online 19 October 2007͒ The properties of ices Ih, II, III, V, and VI at zero temperature and pressure are determined by computer simulation for several rigid water models ͑SPC/E, TIP5P, TIP4P/Ice, and TIP4P/2005͒. The energies of the different ices at zero temperature and pressure ͑relative to the ice II energy͒ are compared to the experimental results of Whalley ͓J. Chem. Phys. 81, 4087 ͑1984͔͒. TIP4P/Ice and TIP4P/2005 provide a qualitatively correct description of the relative energies of the ices at these conditions. In fact, only these two models provide the correct ordering in energies. For the SPC/E and TIP5P models, ice II is the most stable phase at zero temperature and pressure whereas for TIP4P/Ice and TIP4P/2005 ice Ih is the most stable polymorph. These results are in agreement with the relative stabilities found at higher temperatures. The solid-solid phase transitions at 0 K are determined. The predicted pressures are in good agreement with those obtained from free energy calculations. © 2007 American Institute of Physics. ͓DOI: 10.1063/1.2774986͔ I. INTRODUCTION 20th century, starting with the pioneering work of Tammann and Bridgman16–21 up to the recent discovery of ices XII, Taking into account the importance of water, it is not XIII, and XIV.22,23 Compared to the liquid, the study of ices surprising that thousands of simulation studies of water have by computer simulation has been more limited. -
Ice, Ice, Bambino September 8, 2020 1 / 45 Chemistry: 18 Shades of Ice
ICE Chemistry It gets bigger when it freezes! Biology Inupiaq (Alaska) have 100 Stuff lives in it in ice cores! Astrobiology names for ice! Enceladus? Climatology Albedo and Negative feedback Snowball Earth Astrophysics Clear at optical and also radio frequencies Ice as a good cosmic-ray target Cosmic-ray collisions with ice molecules visible from km-scale distances Dave Besson Ice, Ice, Bambino September 8, 2020 1 / 45 Chemistry: 18 Shades of Ice Terrestrial (familiar) ice: ”Ice 1h” 1996: Ice XII discovered 2006: Ice XIII and Ice XIV 2009: Ice XV found extremely high pressures and 143 C. At P>1.55×1012Pa (10M atm) ice!metal Ice, water, and water vapor coexist at the ‘triple point’: 273.16 K (0.01 C) at P=611.657 Pa. 1◦ ≡1/273.16 of difference b/w triple point and absolute zero (this defn will change in May 2019) Dave Besson Ice, Ice, Bambino September 8, 2020 2 / 45 Oddly, ρice < ρwater The fact that ice remains on top of water is what prevents lakes and rivers from freezing upwards from below! Dave Besson Ice, Ice, Bambino September 8, 2020 3 / 45 Socio-Cultural impact: Refrigeration, Curling, Marvel’s Iceman (2015-17) Refrigeration: 400 BC: Persian engineers carve ice in winter and store in 5000 m3 insulated (via ‘sarooj’ - sand, clay, egg whites, lime, goat hair, and ash) caverns in desert during summer Dave Besson Ice, Ice, Bambino September 8, 2020 4 / 45 Why is ice clear (blue) Dave Besson Ice, Ice, Bambino September 8, 2020 5 / 45 and snow white? and implications for climate.. -
The Water Polymorphism and the Liquid–Liquid Transition from Transport Data
Article The Water Polymorphism and the Liquid–Liquid Transition from Transport Data Francesco Mallamace 1,2,* , Domenico Mallamace 3 , Giuseppe Mensitieri 4 , Sow-Hsin Chen 1 , Paola Lanzafame 3 and Georgia Papanikolaou 3 1 Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; [email protected] 2 CNR ISC, UOS Roma Sapienza, Physics Department, Sapienza University of Rome, 00185 Roma, Italy 3 Departments of ChiBioFarAm Section of Industrial Chemistry, University of Messina, CASPE-INSTM, V.le F. Stagno d’Alcontres 31, 98166 Messina, Italy; [email protected] (D.M.); [email protected] (P.L.); [email protected] (G.P.) 4 Department of Chemical, Materials and Industrial Production Engineering, University of Naples Federico II, P.le Tecchio 80, 80125 Napoli, Italy; [email protected] * Correspondence: [email protected]; Tel.: +39-340-233-5213 Abstract: NMR spectroscopic literature data are used, in a wide temperature-pressure range (180–350 K and 0.1–400 MPa), to study the water polymorphism and the validity of the liquid–liquid transition (LLT) hypothesis. We have considered the self-diffusion coefficient DS and the reorientational correlation time tq (obtained from spin-lattice T1 relaxation times), measured, respectively, in bulk and emulsion liquid water from the stable to well inside the metastable supercooled region. As an effect of the hydrogen bond (HB) networking, the isobars of both these transport functions evolve with T by changing by several orders of magnitude, whereas their pressure dependence Citation: Mallamace, F.; Mallamace, become more and more pronounced at lower temperatures. Both these transport functions were D.; Mensitieri, G.; Chen, S.-H.; Lanzafame, P.; Papanikolaou, G. -