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arXiv · 2307.14214

Nuclear quantum effect on the elasticity of ice VII under pressure: A path-integral molecular dynamics study

Jun Tsuchiya·Motoyuki Shiga·Shinji Tsuneyuki·Elizabeth C. Thompson
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Abstract

We investigate the effect of nuclear quantum effects (NQEs) of hydrogen atoms on the elasticity of ice VII at high pressure and ambient temperature conditions using ab initio path-integral molecular dynamics (PIMD) calculations. We find that the NQEs of hydrogen contributes to the transition of ice VII from a static disordered structure to a dynamically disordered structure at pressures exceeding 40 GPa. This transition is marked by a discontinuous increase of the elastic constants. Comparison of ab initio molecular dynamics and PIMD calculations reveal that NQEs increase the elastic constants of ice by about 20% at 70 GPa and 300 K.

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Jun Tsuchiya, Motoyuki Shiga, Shinji Tsuneyuki, Elizabeth C. Thompson. 2023-07-26. Nuclear quantum effect on the elasticity of ice VII under pressure: A path-integral molecular dynamics study. https://doi.org/10.1103/physrevresearch.6.023302

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