Line shape in the low frequency wing of self- and N_2-broadened ν_3 CO_2 lines: temperature dependence of the asymmetry

The shape of the far wing of self- and N(2)-broadened CO(2) lines has been investigated in the 2150-2250-cm(-1) spectral region, i.e., on the low wavenumber side of the lines of the very intense v(3) band of (12)C(16)O(2) in a temperature range of atmospheric interest (200-300 K). The experimental results have been compared to calculated values based on the AFGL 1986 compilation. It appears that a symmetrical sub-Lorentzian line shape based on experiments made on the high wavenumber side cannot reproduce experiments. Comparison with experiments made at room temperature shows that the asymmetry of the correcting line shape factor chi strongly increases when decreasing the temperature.