A kinetic theory of collision-induced depolarized light scattering

The collision-induced depolarized light scattering spectrum arising from the dipole–induced dipole (DID) interactions in atomic fluids has been calculated using kinetic theory methods. The theory contains no adjustable parameters and requires only the temperature, density, and collision diameter as input. Above 25 cm−1, the calculated line shape was found to be in excellent agreement with the spectrum obtained from a hard-sphere molecular dynamics simulation, with the same model for the interaction-induced polarizability. The domain of applicability of the approximations used in reducing the theory to a tractable form was carefully evaluated. The methods developed should be applicable to other intermolecular correlation functions, such as those observed in vibrational relaxation and interaction-induced infrared spectroscopy.