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The relationship between liquid, supercooled and glassy water

Abstract

That water can exist in two distinct ‘glassy’ forms — low- and high-density amorphous ice — may provide the key to understanding some of the puzzling characteristics of cold and supercooled water, of which the glassy solids are more-viscous counterparts. Recent experimental and theoretical studies of both liquid and glassy water are now starting to offer the prospect of a coherent picture of the unusual properties of this ubiquitous substance.

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Figure 1: Schematic illustration of different temperature domains, at atmospheric pressure, of H2O.
Figure 2: Transitions between gas (G), liquid (L), crystal (X) and amorphous (A) phases of water.
Figure 3: Two-phase melting contrasted with one-phase melting.
Figure 4: Thermodynamic behaviour of water predicted by three competing theories.
Figure 5: Detailed version of the projection onto the PT plane of the equilibrium V = V(P, T) surface of Fig. 4c.
Figure 6: The pressure–volume–temperature relation for H2O, on the basis of recent experiments57.
Figure 7: Physical arguments relating to the plausibility of the existence of the known liquid–gas critical point C and the hypothesized LDL–HDL critical point C′.
Figure 8: Effect of the hypothesized LDL–HDL critical point C′ on two constant-pressure paths, a and b, at pressures just below and just at the critical pressure of C′, respectively.

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Acknowledgements

We thank R. J. Hemley, H. Kanno, J. Karbowski, H. Kodama, E. La Nave, R. Sadr-Lahijany, S. Sastry, A. Scala, F. Sciortino, A. Skibinsky, F. W. Starr, Y. Suzuki and M. Yamada for discussions and critical reading of manuscript drafts. This work was supported by the NSF.

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Mishima, O., Stanley, H. The relationship between liquid, supercooled and glassy water. Nature 396, 329–335 (1998). https://doi.org/10.1038/24540

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