Chemical-potential route for multicomponent fluids

TL;DR

This paper develops a chemical-potential based method to analyze multicomponent fluids, providing exact relations and improved equations of state for hard-sphere mixtures, outperforming traditional virial and Boublik-Mansoori-Carnahan-Starling-Starling approaches.

Contribution

It introduces a chemically-based route for deriving thermodynamic properties of multicomponent fluids, enhancing accuracy over existing models.

Findings

The chemical-potential route yields more accurate equations of state.

Application to hard-sphere mixtures shows improved performance.

Interpolation between routes outperforms classical equations.

Abstract

The chemical potentials of multicomponent fluids are derived in terms of the pair correlation functions for arbitrary number of components, interaction potentials, and dimensionality. The formally exact result is particularized to hard-sphere mixtures with zero or positive nonadditivity. As a simple application, the chemical potentials of three-dimensional additive hard-sphere mixtures are derived from the Percus-Yevick theory and the associated equation of state is obtained. This Percus-Yevick chemical-route equation of state is shown to be more accurate than the virial equation of state. An interpolation between the chemical-potential and compressibility routes exhibits a better performance than the well-known Boubl\'ik-Mansoori-Carnahan-Starling-Leland equation of state.