Effects of Dielectric Saturation upon the Diffuse Double Layer and the Free Energy of Hydration of Ions

Abstract

The theory of the diffuse double layer is developed for the case of a dielectric of variable dielectric constant. Using experimental data by Malsch, calculations have been made of the properties of the diffuse double layer. It is found that those properties which are experimentally significant are almost unaffected by the onset of dielectric saturation. The Born equation for the free energy of hydration of ions is elaborated to include the effects of dielectric saturation, and it is found that these effects are negligible in the case of the alkali halide ions.