Correlation effect in spectral line shape from the Doppler to the collision regime

Abstract

The spectral line shape model recently proposed by the present authors [J. Chem. Phys. 109, 8283 (1998)] is extended in order to account for correlation between velocity- and phase-changing collisions. The possible additional source of asymmetry due to the finite duration of collision is also included. In this implemented form, the model is consistent with previous exhaustive experimental studies in the collision regime for H2–rare gases and H2–nitrogen mixtures and has been shown to also accurately describe the observed spectral features at lower pressure for H2–Ar. It should be pertinent for various other molecular systems in a wide range of pressure and temperature, in particular for optical diagnostics.