Combined effect of small- and large-angle scattering collisions on a spectral line shape. (July 2015) - Kochanov, V.P.
Abstract: Algebraic approximations for line profiles calculated on the basis of quantum-mechanical collision integral kernels for dipole–dipole, dipole–quadrupole, and quadrupole–quadrupole intermolecular interaction potentials were obtained. In derivation of the profiles velocity-changing collisions of molecules with scattering on small and large angles also with the speed-dependence of collision relaxation constants have been taken into account. It was shown that the relative contribution of small-angle collisions into the frequency of elastic velocity-changing collisions is much more pronounced for long-range potentials. A sensitive criterion for analysis of a line narrowing was proposed and tested. Highlights: Line profiles are developed with account of soft and hard collisions. Main types of intermolecular interaction were taken into account. A criterion for the analysis of a spectral line narrowing was proposed. Two types of line narrowing were considered.