Accurate equations of state for CF4, CF4–Ar, and CF4–CH4 fluids using two-body and three-body intermolecular potentials from molecular dynamics simulation

Abstract

Molecular dynamics simulations have been performed to obtain pressures and equations of state of CF4, CF4–Ar, and CF4–CH4 fluids using different inversion and ab initio pair-potentials. To take many-body forces into account, the three-body potentials of Hauschild and Prausnitz, Mol. Simul. 11 (1993) 177–185, Wang and Sadus, J. Chem. Phys. 125 (2006) 144509–144513, and Guzman et al., Mol. Phys. 109 (2011) 955–967 have been used with the pair-potentials. The significance of this work is that the many-body potential of Hauschild and Prausnitz is extended as a function of density, temperature, and molar fraction and is used with the HFD-like pair-potentials of CF4, CF4–Ar, and CF4–CH4 systems to improve the prediction of the pressure values without requiring an expensive three-body calculation. We have also simulated the self-diffusion coefficient of CF4 in good agreement with experimental data.