The shapes of the extreme wings of self-broadened CO2(lines have been investigated)in three spectral regions near 7000, 3800, and 2400 cm-1. Absorption measurements have been made on the high-wavenumber sides of band heads where much of the absorption by samples at a few atm is due to the extreme wings of strong lines whose centers occur below the band heads. New information has been obtained about the shapes of self-broadened CO2 lines as well as CO2 lines broadened by N2, O2, Ar, He, and H2. Beyond a few cm-1 from the line centers, all of the lines absorb less than Lorentz-shaped lines having the same half-widths. The deviation from the Lorentz shape decreases with increasing wavenumber, from one of the three spectral regions to the next. The absorption by the wings of H2- and He-broadened lines is particularly low, and the absorption decreases with increasing temperature at a rate faster than predicted by existing theories.
