Research note: Simulation and model testing of size asymmetric non-additive hard spheres

Molecular dynamics simulation results for the compressibility factor of size asymmetric nonadditive hard spheres are reported. Three recently proposed mixture models and the van der Waals one-fluid theory are tested against the simulation data. It is found that the van der Waals theory is totally inadequate for mixtures with large non-additivity or size difference at high densities. The recent models are satisfactory in general. The one model that satisfies exact consistency relationships is the most accurate.