Statistical Mechanical Theory of Thermal Diffusion in Binary Liquid Solutions

Abstract

The statistical mechanical theory of thermal diffusion in binary solutions is developed from the point of view of the pair space linear relations which have been used previously to derive theories of the heat of transport and thermal conductivity. The thermal diffusion factor is obtained in terms of statistical mechanical averages over the equilibrium radial distribution functions, and when assumptions of the theory of regular solutions are introduced into the general expression, we find that it is related to the molar volumes, thermal expansion coefficients and compressibility coefficients of the pure components and to the self‐diffusion coefficients in the mixture.