Ion-pair theory of concentrated electrolytes. II. Approximate dielectric response calculation

Abstract

The theoretical program initiated in the preceding paper is continued. The wavelength-dependent dielectric response function for the "primitive- model" electrolyte, ε(k), is evaluated by means of a self-consistent torque calculation for ion pairs in an external field. The result is used to obtain the longest-ranged component of the ion-atmosphere charge density. The rigorous second-moment condition on the ion atmosphere then is used to compute crudely the short-ranged components. Besides the usual low-concentration terms, the implied free energy [Eq. (76)] and activity coefficient [Eq. (77)] contain negative terms varying with the four-thirds power of concentration.