A new intermolecular potential for liquid oxygen

We develop a new two-site Lennard-Jones intermolecular potential model for liquid oxygen where the two sites are centered on the nuclear positions. The Lennard-Jones ϵ and σ parameters are determined by fitting experimental thermodynamic data in the liquid region of the phase diagram to results from molecular dynamics simulations. This procedure yields ϵ/k=48 K, and σ=3.006 Å. Using this potential we then calculate, again from molecular dynamics simulations, the static structure factor (or site–site radial distribution function) and the second-rank rotational time-correlation function. In both cases our results are in excellent agreement with experiment (from X-ray scattering and depolarized Raman spectroscopy, respectively).