Reference system selection and average Mayer-function perturbation theory for molecular fluids

Abstract
A perturbation theory for molecular fluids due to Smith, and Perram and White is analysed and equations are presented in a computationally convenient form for determining the full angular-dependent pair correlation function. The discussion centres on the most appropriate choice of reference system and we use the Mayer function as expansion functional. The implications of the resulting RAM (reference system average Mayer-function expansion) theory are discussed.