Theoretical O₂- and N₂-Broadening Coefficients of CH₃Cl Spectral Lines

The intermolecular potential derived by Leavitt from irreducible tensor methods is used in a semiclassical impact theory to calculate the O- and N-broadening coefficients of the P(J, K) and R(J, K) lines belonging to a parallel band of CHCl. To describe the trajectory model, we have used a Lennard-Jones isotropic potential. The parameters of this potential have been calculated for CHCl, O, and N by fitting experimental values of second-virial coefficients. By choosing some of the potential parameters among values available in the literature, we have obtained results that are generally in satisfactory agreement with experimental data. Our calculation predicts that for the lines belonging to the same low or medium J transitions, the broadening coefficients decrease significantly as K increases, especially for CHCl-N.