Effects of stacking disorder on thermal conductivity of cubic ice

Abstract

This is the published version of a paper published in J. Chem. Phys. Citation for the original published paper (version of record):Johari,G.P., Andersson, O. (2015) Effects of stacking disorder on thermal conductivity of cubic ice J. Chem. Phys., 143, 054505 (2015).Access to the published version may require subscription. N.B. When citing this work, cite the original published paper. Cubic ice is said to have stacking disorder when the H 2 O sequences in its structure (space group Fd3m) are interlaced with hexagonal ice (space group P6 3 /mmc) sequences, known as stacking faults. Diffraction methods have shown that the extent of this disorder varies in samples made by different methods, thermal history, and the temperature T, but other physical properties of cubic and hexagonal ices barely differ. We had found that at 160 K, the thermal conductivity, κ, of cubic ice is ∼20% less than that of hexagonal ice, and this difference varies for cubic ice samples prepared by different methods and/or subjected to different thermal history. After reviewing the methods of forming cubic ice, we report an investigation of the effects of stacking disorder and other features by using new data, and by analyzing our previous data on the dependence of κ on T and on the pressure. We conclude that the lower κ of cubic ice and its weaker T-dependence is due mainly to stacking disorder and small crystal sizes. On in situ heating at 20-50 MPa pressure, κ increases and cubic ice irreversibly transforms more sharply to ice Ih, and at a higher T of ∼220 K, than it does in ex situ studies. Cooling and heating between 115 and 130 K at 0.1 K min −1 rate yield the same κ value, indicating that the state of cubic ice in these conditions does not change with time and T. The increase in κ of cubic ice observed on heat-annealing before its conversion to hexagonal ice is attributed to the loss of stacking faults and other types of disorders, and to grain growth. After discussing the consequences of our findings on other properties, we suggest that detailed studies of variation of a given property of cubic ice with the fraction of stacking faults in its structure may reveal more about the effect of this disorder. A similar disorder may occur in the mono-layers of H 2 O adsorbed on a substrate, in bulk materials comprised of two dimensional layers, in diamond and in Zirconium and in numerous other crystals. C 2015 AIP Publishing LLC. [http://dx

Thermodynamic Analysis of the Two-Liquid Model for Anomalies of Water, HDL–LDL Fluctuations, and Liquid–Liquid Transition

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Structure of ice confined in carbon and silica nanopores

“…It is considered that the formation of cubic structures, rather than hexagonal structures, in the pores can be attributed to the restrictions on the size of the crystallite. However, according to recently published studies [4,10,[28][29][30][31], the cubic form that has been observed is not exactly cubic. This form of ice, so-called cubic phase, shows stacking faults instead of an ordered arrangement of two-dimensional layers [28].…”

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Dynamic signatures of the transition from stacking disordered to hexagonal ice: Dielectric and nuclear magnetic resonance studies

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