The influence of rotational relaxation on the unresolved Q-branch density-shift induced by vibrational dephasing Original Research Article

The density dependence of the contributions of elastic vibrational dephasing and rotationally inelastic collisions into the overall shift of the Raman Q-branch profile of nitrogen has been theoretically studied. The results have been found to accurately reproduce the frequency shift measurements over a wide density range (10–900 amagat), also including the liquid phase.