Abstract
The binary diffusion coefficient D 12 of various substances measured at high dilution in dense CO2 is not describable by the Enskog-Thorne approach. A simplified model potential is presented here, which allows the simulation of the D 12 and the thermodynamic properties of the system CO2/C6H6 by molecular dynamics calculations over a wide range of density of CO2. The failure of the Thorne equation is attributed mainly to the neglect of the attractive interactions in dense gases.