Molecular Dynamics Simulation of the Maxwell-Stefan Diffusion Coefficients in Lennard-Jones Liquid Mixtures

Abstract

Maxwell-Stefan (MS) diffusion coefficients in multicomponent liquids have been determined by the equilibrium molecular dynamics calculation of the appropriate Green-Kubo equation. Simulations were performed for systems of 300 LJ particles at various compositions. The unary system was divided into three components by attaching a colour label to the particles, which plays no role in the dynamics. The binary system argon + krypton was divided into three species by attaching a colour label to the particles of argon. The ternary system consisted of argon, krypton and neon. The results of the calculation of the MS diffusion coefficients in the unary and binary systems agreed well with the literature values. The MS diffusion coefficients of the unary system did not differ significantly from the self-diffusion coefficient. The MS diffusion coefficients of the ternary system behaved as expected from other physical properties.

Key Words:

• Molecular dynamics
• Green-Kubo method
• Maxwell-Stefan diffusion coefficients
• LJ liquid mixtures