Volume‐Explicit Equation of State and Excess Volume of Mixing of Fused‐Hard‐Sphere Fluids

The paper presents a simple analytic volume‐explicit equation of state (EOS) for fluids of hard bodies made up to fused hard spheres (FHS). Application of this EOS to both pure fluids and fluid mixtures (via Amagat's law) provides an accurate description of practically all existing computer simulation data. It is found that deviations from the assumption of ideal mixing are restricted essentially to low densities only; at higher densities small deviations are detected only for quite large volume ratio of molecules while the shape does not seem to play a significant role.