Multipolar electrolyte solution models. III. Free energy of the charged and dipolar hard sphere mixture

Abstract

Helmholtz free energies, internal energies, and pressures of mixtures of charged and dipolar hard spheres are obtained from Monte Carlo computer simulation. Ionic and solvent contributions to these properties of this electrolyte solution model are reported for a large number of states, with variations in total density, ionic concentration, and the ratio of ionic charge to solvent polarity. From this data we show that, in contrast to solution theories based on replacement of the solvent by a continuum with dielectric constant ε0, there is a correspondence in properties of states at fixed κ02=κ2ε0, where κ is the inverse Debye length.