Cross Second Virial Coefficients and Dilute Gas Transport Properties of the Systems (CO2 + C2H6) and (H2S + C2H6) from Accurate Intermolecular Potential Energy Surfaces

The cross second virial coefficients and dilute gas shear viscosities, thermal conductivities, and binary diffusion coefficients of the systems (CO2 + C2H6) and (H2S + C2H6) were determined with high accuracy at temperatures from (150 to 1200) K by means of statistical thermodynamics and the kinetic theory of polyatomic gases. The required intermolecular potential energy surfaces (PESs) for the CO2–C2H6 and H2S–C2H6 interactions are presented here, while the like-species interactions were modeled employing PESs developed previously as part of our studies on the pure gases. All PESs are based on high-level quantum-chemical ab initio computations and are represented analytically by site–site potential functions. The agreement between the calculated values for the investigated mixture properties and the few reliable experimental data is very satisfactory.