A further test of the Boublik et al equations for binary hard sphere mixtures

The Boublik-Mansoori-Carnahan-Starling-Leland (BMCSL) equation of state is examined for binary hard sphere mixtures. It is argued that this equation of state is reliable for a large diameter ratio. Monte Carlo (MC) simulations are performed for many states, some of high density and large diameter ratio. Al moderate densities away from the solid-liquid transition, the MC results show reasonably good agreement with the BMCSL's prediction of the compressibility factor. This confirms the earlier findings of Jackson et al. for the validity of BMCSL in the liquid phase. The failure of the BMCSL prediction in some states is due to proximity to the solid-liquid transition and not due to the large diameter ratio. The individual pair distribution functions predicted by the BMCSL in all cases, however, can be poor, especially, for a pair of large spheres at very low concentration. Comparison of the MC distribution functions and those predicted by several theories are made.