Vol. 34, issue 09, article # 2

Buldyreva J. V., Troitsyna L. A., Dudaryonok A. S., Lavrentieva N. N. Broadening coefficients of methyl iodide vibrotational lines induced by nitrogen, oxygen and air pressure. // Optika Atmosfery i Okeana. 2021. V. 34. No. 09. P. 676–681. DOI: 10.15372/AOO20210902 [in Russian].
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The nitrogen-, oxygen and air-broadening coefficients of CH3I lines in the n6 band (RP-, PP-, RQ-, PQ-, RR-, and PR-sub-branches) are calculated at room temperature with the rotational quantum numbers 0 ≤ J ≤ 70, 0 ≤ K ≤ 20. Calculations are performed by two methods: the semi-classical method with exact trajectories, adapted for the case of an absorbing molecule such as a symmetric top, colliding with a diatomic homonuclear partner, and the semi-empirical method based on the impact semi-classical theory and using an empirically adjusted factor for the efficiency functions. When comparing with recently published experimental data, a good agreement was obtained for the semi-empirical approach, so that the half-widths can be calculated by this method for reliable use in atmospheric applications.


line profile, line-broadening, symmetric top, methyl iodide


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