Thermal transport coefficients including the Soret coefficient for various liquid Lennard-Jones mixtures

Publisher Website
Google Scholar
Abstract
Thermal-transport coefficients have been determined for binary-liquid Lennard-Jones mixtures composed of strongly different component particles by equilibrium molecular-dynamics calculations. Two very unequal types of mixtures have been considered. The first type contained systems of particles of different interaction strength and equal ‘‘volume,’’ while the second type was comprised of systems of particles of different ‘‘volume’’ and equal interaction strength. For both mixture types, the 1-2 interaction potentials of the unlike pairs of particles have been varied systematically. We have chosen the Lennard-Jones potential parameters such that the mixtures with average 1-2 interaction showed nearly the same values for the mutual-diffusion coefficient, the shear and the bulk viscosity coefficients, as well as the thermal conductivity coefficient. This facilitated a comparison of the thermal diffusion coefficients of both types of systems. It was found that the latter coefficient differed drastically in magnitude and sign. On the other hand, the coefficient appeared to be rather insensitive to alterations of the 1-2 interaction, whereas the diffusion and viscosity coefficients showed considerable dependence on them.