DIELECTRIC RELAXATION IN LIQUIDS: I. THE REPRESENTATION OF RELAXATION BEHAVIOR

Abstract

Methods are described for the determination from experimental data of the parameters used in the skewed-arc representation in the complex dielectric constant plane of dielectric relaxation in liquids. Graphs give the frequency dependence of the real and imaginary parts of the dielectric constant predicted by the skewed-arc equation. Evidence, which includes an analysis of published data and of some new data, is presented for the frequent occurrence of this type of relaxation behavior in liquids. The resolution of the effects of different relaxation processes is discussed.The recent defect-diffusion model of Glarum is found to lead, under some conditions, to complex dielectric constant loci which are practically indistinguishable from skewed-arc loci over much of the frequency range of dispersion. It predicts departures from skewed-arc behavior at relatively high frequencies which are possibly related to experimentally observed departures.It is concluded that skewed-arc characteristics arise from the presence of co-operative relaxation processes, possibly aided by the diffusion of disordered regions, in which the individual mechanisms of relaxation cannot be resolved by application of the superposition principle.