A molecular dynamics simulation of sulphur hexafluoride

Abstract

Molecular dynamics simulations are performed for the six-centre Lennard-Jones model of SF₆ over a temperature range from 225 to 398 K and density from 1·3 to 1·9 g cm^-3. The results of simulations are in good agreement with experimental data for the translational diffusion coefficient and correlation times for molecular reorientation and angular momentum, except for the highest temperature where small discrepancies between the simulated and experimental values for the diffusion coefficients are observed. Theoretical models for time correlation functions of molecular reorientations are compared with computer simulation results. It is found that the J-diffusion model reproduces the rotational correlation function of SF₆ more satisfactorily than other models.