Absorption and refraction of radiation by liquids. I. Refraction by pure liquids

Abstract

Expressions for the dielectric constant of a pure liquid are obtained from quantum electrodynamics, and compared with those obtained from electrostatic arguments. The Lorentz cavity field is shown to be associated with off-resonance intermolecular exchange of excitation. An application of perturbation theory up to a level including such excitation exchange leads to the Debye equation for pure non-polar liquids, and an analogue of the Onsager equation for polar liquids.