Experimental and theoretical study of line mixing in methane spectra. III. The Q branch of the Raman ν1 band

摘要: The shape of the ν1 Raman Q branch CH4 perturbed by Ar and He at room temperature has been studied. Stimulated spectroscopy (SRS) experiments have made in 2915–2918 cm−1 spectral region for total pressures from 0.4 to 70 atm mixtures ≈5% with Ar. Analysis spectra demonstrates that is significantly influenced line mixing much narrower than what predicted addition individual profiles. For first time, a model proposed calculation analysis effects collisions on considered spectra. In this approach, rotational part relaxation matrix constructed, no adjustable parameter, starting semiclassical state-to-state rates. Two empirical constants which account shift broadening due vibrational are introduced their values determined fits measured Comparisons between measurements results computed wit...