On the shape of the Q-branch of Raman scattering spectra in dense media. Anisotropic scattering

The Q-branch width of the anisotropic Raman spectrum for linear molecules has been shown to increase with density. Until the overlap of the O-, Q-, S-branches is small, the product of the half-widths of isotropic and anisotropic Q-branches, in units of mean frequency, is a constant characterizing the collision strength.