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arXiv · 2309.05427

Pressure of Coulomb systems with volume-dependent long-range potentials

A. S. Onegin·G. S. Demyanov·P. R. Levashov
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Abstract

In this work, we consider the pressure of Coulomb systems, in which particles interact via a volume-dependent potential (in particular, the Ewald potential). We confirm that the expression for virial pressure should be corrected in this case. We show that the corrected virial pressure coincides with the formula obtained by differentiation of free energy if the potential energy is a homogeneous function of particle coordinates and a cell length. As a consequence, we find out that the expression for pressure in the recent paper by J. Liang \textit{et al.} [\href{https://doi.org/10.1063/5.0107140}{J. Chem. Phys. \textbf{157}, 144102 (2022)}] is incorrect.

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A. S. Onegin, G. S. Demyanov, P. R. Levashov. 2023-09-11. Pressure of Coulomb systems with volume-dependent long-range potentials. https://arxiv.org/abs/2309.05427

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