Equation of state for the hard sphere fluids

Can Cui; Jianxiang Tian

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arXiv · 2512.05488

Equation of state for the hard sphere fluids

Can Cui·Jianxiang Tian

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Abstract

Based on the survey of the literatures on the new improvements on the equation of state (EOS) for the hard sphere fluids, we here compare lots of different EOSs and present a very accurate equation of state for this kind of fluids. The new equation is built up on the basis of (1) the best estimated virial coefficients B5-B11 by Tian et al. [ Phys. Chem. Chem. Phys., 2019, 21, 13070] and (2) the newest numerical simulation data of the compressibility factor versus the density by Pieprzyk et al. [Phys. Chem. Chem. Phys., 2019, 21, 6886]. Our results show that this equation is accurate in not only the stable density range but also the metastable density range with the proper closest packing fraction pole, and well derives the predictive values of the high order virial coefficients B13-B16.

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Can Cui, Jianxiang Tian. 2025-12-05. Equation of state for the hard sphere fluids. https://arxiv.org/abs/2512.05488

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