On some empirical expressions for the contact values of the pair distribution functions and fluid—fluid phase separation in hard sphere mixtures

Abstract

The fluid-fluid binodal of asymmetric hard sphere mixtures obtained from approximate expressions of the virial pressure is investigated. Also the behaviour of the Gibbs free energy following from particular combinations of standard expressions of the contact values of the pair distributions functions is examined. A recently proposed parametrization of the latter in the colloidal limit is then discussed and compared with existing simulation data for the binodal of the effective fluid.