Empirical intermolecular potential from depolarized interaction-induced light scattering spectra for tetrafluoromethane

Abstract

Depolarized interaction-induced light scattering spectra of tetrafluoromethane in the frequency range 2–150 cm −1 at 294.5 K and 0.91 mol/l with the interaction pressure virial coefficient and viscosity have been used for deriving the empirical multiparameter Morse–Morse–Morse–Spline–van der Waals (M3SV), Lennard-Jones, Kihara, and exp-6 intermolecular potentials. The line shape at relatively low frequencies is determined largely by the effect of bound and free transitions. At intermediate frequencies it is sensitive to both the attractive part of the potential and the short-range part of the polarizability anisotropy. The high frequency wings are discussed in terms of the collision-induced rotational Raman effect and estimates for the dipole–quadrupole and dipole–octopole polarizabilities A and E, respectively, are obtained. Absolute zeroth and second moments have been measured and compared with theoretical calculations using these models of the intermolecular potentials. The results show that M3SV is the most accurate potential yet reported for this system.