Collision-induced light scattering and absorption in atoms and symmetric molecules: A spherical tensor approach

The theory of collision-induced light scattering in atoms and symmetric molecules is presented using the formalism of spherical tensors. Resulting expressions for the intensity for first and second-order interactions are implemented in the programming language "Mathematica" and results for the depolarization ratio as well as isotropic and anisotropic components to the scattering intensity are presented. Experimental results are shown of the absorption spectrum of water vapour in the far infrared, from 50 to 600 wavenumbers, with a nitrogen perturber. Finally, a novel new formulation of the depolarization ratio based on only tensor ranks is presented.