Electric Polarization of Onsager Fluids. II. Birefringence. 3. Role of Universal Pairwise Interactions

A comparative analysis of several methods of interpretation of solvent influence on molar Kerr constants of solutes was done. The analysis was based on experimentally determined electro-optical and dielectric properties of binary solutions of organic substances with various polarities, polarizabilities and optical anisotropies. It was found that the role of universal van-der-Waals interactions treated via London-Debye-Keesom potentials was best accounted for by a modified orientational theory of Kerr effect that developed the ansatz of reactive field and local dielectric permittivity. An extrapolation method of determination of gas phase molar Kerr constants of solutes was deduced from the theory.