The potential model dependence of the neutron radial and partial distribution functions for liquid CO₂

Abstract

The neutron intermolecular radial distribution functions g_m (r) of liquid CO₂ (at T ⋍ 222 K, θ = 1·15 g cm^-3) have been computed for four different potential models, namely a two-centre Lennard-Jones potential with and without point quadrupole, a three-centre Lennard-Jones with point quadrupole and the partially ‘ab initio’ potential recently proposed by Böhm and Ahlrichs.

The features of the radial distribution functions g_m (r) are discussed in terms of the partial site-site distribution functions g _ij(r) and the important role of the electrostatic interactions is stressed. The two- and three-centre Lennard-Jones potentials with point quadrupole satisfactorily reproduce the main features of the experimental radial distribution function.