Absorption coefficient in the infrared CO2 Q-branch

The values of absorption coefficient κ in the wings of the infrared CO 2 Q-branches significantly differ from those isolated Lorentzian lines. It becomes now traditional to explain these deviations by line-mixing. Actually, presence of the small line separations in the Q-branches are greatly conductive to this point of view. It can be noted, however, that the largest deviations from the Lorentzian line calculations are observed in spectral regions comparatively far from the line centers. Therefore it would be interesting to know whether the line wing theory can be used to describe the observed frequency dependence of κ or not. The present study concerns with the CO 2 Q-branch at 1932cm -1 .