Perturbation theory and the equilibrium structure of simple liquids

Monte Carlo studies of the reference fluid used by Chandler, Weeks, and Andersen (CWA) are reported. Although the CWA theory gives good values for the total thermodynamic properties, in its original form it gives less satisfactory values for the individual terms in their perturbation expansion. This results in part from the use of the Percus-Yevick theory in the CWA calculation of the radial distribution function. © 1971 The American Physical Society.