Liquid structure of halomethanes

Abstract

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 dichlorodifluoromethane (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 complementary molecular dynamics simulations on the molecules. The intermolecular structure has been interpreted in terms of the various possible arrangements of molecules that can occur in the liquid state. The intermolecular potentials obtained from the simulations of these molecules have been compared to establish the transferability of potential parameters between molecules of this type; the results show that the ability to transfer parameters between molecules appears to have as much to do with the symmetry of the molecule as with the atoms present.

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