A perturbation theory of hard quadrupolar fluids

Abstract

A perturbation theory, derived by Boublik, for the polar hard Gaussian overlap model is extended to other hard polar models. The final equations are simple, and good agreement between theory and simulation is found for quadrupolar hard dumbbells and for quadrupolar hard spherocylinders. Since there are no simulation data for quadrupolar hard spherocylinders, we have carried out some Monte Carlo simulations for this system at two different elongations. For quadrupolar hard spheres the theory presented is identical with a previous treatment of Patey and Valleau. Therefore the proposed perturbation theory can be applied to spherical, linear or nonlinear hard quadrupolar fluids, showing good agreement with the simulation results in all the cases.