Rotationally inelastic rates and Raman Q-branch linewidths for N2+ N2

Abstract

The infinite order sudden (IOS) approximation is used to calculate rate constants for rotationally inelastic scattering of two N2 molecules. A new approximation, which is a modified version of the breathing sphere approximation, is introduced. Rate constants obtained using this approximation are compared with those of the IOS approximation. Both sets of rate constants are then summed up over all final rotational levels of the perturbed molecule in order to determine Raman Q-branch spectral linewidths. These theoretical linewidths are compared with experimental linewidths. Good agreement is obtained for higher temperatures.