Computation of some thermodynamic, structural, and transport properties of fluid oxygen using two-body and three-body intermolecular potentials from molecular dynamics simulation

Abstract

We have performed molecular dynamics (MD) simulation to obtain pressure, internal energy, radial distribution function, and self-diffusion coefficient of fluid oxygen using effective two-site Lennard-Jones (2SLJ) and two-body Hartree–Fock dispersion (HFD)-like potentials. To take higher-body forces into account, we have used three-body potentials of Hauschild and Prausnitz [T. Hauschild, J.M. Prausnitz, Molec. Simul. 11 (1993) 177] and Miyano [Y. Miyano, Fluid Phase Equilib. 104 (1995) 71] with the two-body HFD-like potential. We have also considered the spin correction in our simulation which improved our energy results. The significance of this work is that the three-body potential of Hauschild and Prausnitz extended as a function of density and temperature and can be used with the HFD-like potential to improve the prediction of the pressures of fluid oxygen without requiring an expensive three-body calculation. The molecular dynamics simulation of oxygen has been also used to determine a new equation of state.