Calculation of infinite-dilution partial molar properties by computer simulation

Partial molar properties at infinite dilution for binary Lennard‐Jones mixtures are calculated using Monte Carlo simulation methods. The variation of these properties with density, temperature, and intermolecular force parameters is systematically studied. Simulation pair correlation functions are used to examine the structure of the mixtures at the molecular level. Results are also compared to predictions of the van der Waals I conformal solution theory. Partial molar volume and internal energy are found to be strongly dependent on the isothermal compressibility of the mixture and on the proximity of the mixture state condition to phase boundaries. The van der Waals I conformal solution theory gave good results for the infinite‐dilution chemical potential μ 1∞ and reasonable results for the partial molar internal energies and volumes. However, it is suspected that this is limited to the infinite‐dilution case, where the isothermal compressibility of the mixture is well represented by the pure‐fluid equation of state.