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arXiv · 2109.08766

Structure of high-pressure supercooled and glassy water

Riccardo Foffi·Francesco Sciortino
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Abstract

We numerically investigate the metastable equilibrium structure of deep supercooled and glassy water under pressure, covering the range of densities corresponding to the experimentally produced high-density and very-high-density amorphous phases. At $T = 188$ K, a continuous increase in density is observed on varying pressure from $2.5$ to $13$ kbar, with no signs of first-order transitions. Exploiting a recently proposed approach to the analysis of the radial distribution function -- based on topological properties of the hydrogen-bond network -- we are able to identify well-defined local geometries that involve pair of molecules separated by multiple hydrogen bonds, specific of the high and very high density structures.

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Riccardo Foffi, Francesco Sciortino. 2021-09-17. Structure of high-pressure supercooled and glassy water. https://doi.org/10.1103/physrevlett.127.175502

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