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arXiv · 2205.00063

Comparing four hard-sphere approximations for the low-temperature WCA melting line

Eman Attia·Jeppe C. Dyre·Ulf R. Pedersen
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Abstract

By combining interface-pinning simulations with numerical integration of the Clausius-Clapeyron equation we determine accurately the melting-line coexistence pressure and fluid/crystal densities of the Weeks-Chandler-Andersen (WCA) system covering four decades of temperature. The data are used for comparing the melting-line predictions of the Boltzmann, Andersen-Weeks-Chandler, Barker-Henderson, and Stillinger hard-sphere approximations. The Andersen-Weeks-Chandler and the Barker-Henderson theories give the most accurate predictions, and they both work excellently in the zero-temperature limit for which analytical expressions are derived here.

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Eman Attia, Jeppe C. Dyre, Ulf R. Pedersen. 2022-04-29. Comparing four hard-sphere approximations for the low-temperature WCA melting line. https://doi.org/10.1063/5.0097593

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