Dielectric studies of non-electrolyte solutions. Part 2.—Non-linear behaviour of associated liquids. Application to the study of pyridine–chloroform interactions

Abstract

The molecular theory of dielectric properties of liquid mixtures proposed earlier is extended to cases in which the components of the liquid interact chemically.

The chemical equilibrium modifies the non-linear behaviour. The resulting equation provides the possibility of adding non-linear measurements to ordinary dielectric studies of associated liquids and therefore to investigate molecular interactions in more detail.

The study of pyridine + chloroform mixtures is carried out as an example. Variations of equiibrium constant with the electric permittivity of the liquid are observed. They explain discrepancies between results obtained by different techniques (i.r., n.m.r.). Variation of the electrostatic part of the solvation energy explains this phenomenon satisfactorily.