Barker–Henderson theory as an accurate theory of simple mixtures

Abstract

The properties and excess properties of some simple binary mixtures have been calculated from the Lennard-Jones potential and the Barker–Henderson (BH) theory including the second order terms. In these calculations the radial distribution function was approximated by the Percus–Yevick g(R) value combined with the corrections devised by Verlet and Weis and Lee and Levesque. The results show that these corrections eliminate most of the major differences between the Monte Carlo values and the BH theory values obtained previously but in some cases lead to small increases in errors for then excess properties of some mixtures. The comparisons with experimental data while generally qualitatively correct showed greater uncertainties as the interaction potentials and their mixing rules are unspecified for these systems.