Influence of dielectric friction on molecular reorientations

Abstract

A theory is presented about the effects of dielectric friction on the reorientation of a polar molecule undergoing rotational diffusion. In contrast to previous treatments, the torque on the molecular dipole is calculated in a way which accounts for the time dependence of the molecular orientations and is nevertheless consistent with the expression for the instantaneous reaction field. The results obtained permit an estimate to be made of the influence of dielectric friction on the values of the correlation times and on the frequency behaviour of the real and imaginary components of the complex permittivity.