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Equation of state of non-additive $d$-dimensional hard-sphere mixtures

A. Santos·M. Lopez de Haro·S. B. Yuste
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Abstract

An equation of state for a multicomponent mixture of non-additive hard spheres in $d$ dimensions is proposed. It yields a rather simple density dependence and constitutes a natural extension of the equation of state for additive hard spheres proposed by us [A. Santos, S. B. Yuste, and M. López de Haro, Mol. Phys. 96, 1 (1999)]. The proposal relies on the known exact second and third virial coefficients and requires as input the compressibility factor of the one-component system. A comparison is carried out both to another recent theoretical proposal based on a similar philosophy and to the available exact results and simulation data in $d=1$, 2, and 3. Good general agreement with the reported values of the virial coefficients and of the compressibility factor of binary mixtures is observed, especially for high asymmetries and/or positive nonadditivities.

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A. Santos, M. Lopez de Haro, S. B. Yuste. 2004-10-22. Equation of state of non-additive $d$-dimensional hard-sphere mixtures. https://doi.org/10.1063/1.1832591

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