2018/11/14 by Shinji Saito, Biman Bagchi, Saito, Shinji +1
Materials Science · #FOS: Physical sciences #Glass properties and applications #Material Dynamics and Properties #Soft Condensed Matter (cond-mat.soft)
paper · pdf · doi:10.48550/arxiv.1811.05643
openalex publication_date 2018/11/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Frequency dependent specific heat, introduced by Grest and Nagel, offers\nvaluable insight into the vitrification of supercooled liquid. We calculate\nthis quantity and other thermodynamic properties of supercooled liquid water by\nvarying temperature and density across the "no man's land" all the way to the\nformation of amorphous ice. The calculations are aided by very long computer\nsimulations, often more than 50 \μ s long. Density fluctuations that arise\nfrom the proximity to a putative liquid-liquid (LL) transition at 228 K, cast a\nlong shadow on the properties of water, both above and below the LL transition.\nWe carry out the calculation of the quantum mechanical static and\nfrequency-dependent specific heats by combining seminal works by Lebowitz,\nPercus, and Verlet and Grest and Nagel with the harmonic approximation for the\ndensity of states. The obtained values are in quantitative agreement with all\navailable experimental and numerical results of specific heats for both\nsupercooled water and ice. We calculate the entropy at all the state points by\nintegrating the specific heat. We find that the quantum corrected-contributions\nof intermolecular vibrational entropy dominate the excess entropy of amorphous\nphases over the crystal over a wide range of temperature. Interestingly, the\nvibrational entropy lowers the Kauzmann temperature, T rm K, to 130 K,\njust below the experimental glass-to-liquid water transition temperature,\nT rm g, of 136 K and the calculated T rm g of 135 K in our previous\nstudy. A straightforward extrapolation of high temperature entropy from 250 K\nto below however would give a much higher value of T rm K \∼ 190 K.\nThe calculation of Lindemann ratios places the melting of amorphous ice \∼\n135 K. The amorphous state exhibits an extremely short correlation length for\nthe distance dependence of orientational correlation.\n