CALCULATION OF DIPOLE AUTOCORRELATION FUNCTION FOR A SYSTEM OF WEAKLY COUPLED ELECTRIC DIPOLES

In this paper, we present a simple theoretical treatment of dipolar relaxation, essentially based on the autocorrelation formalism and derived from the general theory developed by Boon and Rice for the autocorrelation function of a dynamical variable. A simple model is introduced to derive analytical expressions for the dipolar autocorrelation function, from which other quantities, like the response function and the complex dielectric function, are calculated. These theoretical results are tested against the experimental data obtained from a molecular dynamics study by Bellemans, Köhler, and Gancberg on a two-dimensional system of electric dipoles on a rigid lattice, subject to dipole-dipole interactions. We also append some results concerning the memory function governing the evolution of the autocorrelation function as described by the master equation.