Calculation of the Dielectric Constant of a Fluid by Cluster Expansion Methods

Abstract

Corrections are obtained to the Clausius—Mossotti—Debye formula for the dielectric constant of a fluid of polar but nonpolarizable molecules by a cluster method. The calculation shows the contributions to the moment of the sample which depend upon the size (and presumably also the shape) of the sample explicitly. A new term, not found in other treatments, is obtained in the third order of the expansion of the Clausius—Mossotti function in powers of μ² which represents the effect of the exclusion of third molecules from between a pair which is close together.