An Analysis of the Pressure Dependence of the Dielectric Constant of Polar Liquids

The Onsager and Kirkwood theories of polar liquids have been used to analyze the available experimental data on the pressure dependence of the dielectric constant. It is found necessary in most cases to assume an appreciable decrease in the dipole moment arising from intramolecular distortion which may be large enough in some cases to more than compensate for the increase in effective moment caused by intermolecular compression. Quantitative estimates of these two factors are given, and their influence on binding energy and compressibility is discussed.