CO2-water supercritical mixtures:: Test of a potential model against neutron diffraction data

A neutron diffraction experiment on supercritical mixtures of water and CO2 at two concentrations is presented. Data are analyzed within the EPSR framework and the water-water and water-CO2 radial distribution functions are compared with those calculated by a Molecular Dynamics simulation performed by using the TIPS2 and EPM-M potential models for water and CO2 respectively. It is found that the Molecular Dynamics simulation reproduces the overall shape of the site-site radial distribution functions, although missing a few subtle changes brought along when the CO2 concentration is increased. (c) 2007 Elsevier B.V. All rights reserved.