LIQUID STRUCTURE OF HALOMETHANES

Neutron scattering experiments have been performed on the liquid state of a variety of halomethanes; the results for bromotrifluoromethane ( CBrF3, R13B1), chlorotrifluoromethane (CClF3, R13) and, dichlorodifluo romethane (CCl2F2, R22) are presented. The intramolecular structure of these molecules has been obtained directly from the neutron data and the intermolecular structure has been extracted by performing compleme ntary molecular dynamics simulations on the molecules. The intermolecu lar structure has been interpreted in terms of the various possible ar rangements of molecules that can occur in the liquid state. The interm olecular potentials obtained from the simulations of these molecules h ave been compared to establish the transferability of potential parame ters between molecules of this type; the results show that the ability to transfer parameters between molecules appears to have as much to d o with the symmetry of the molecule as with the atoms present.