Total absorptance ∫ A(ν)dν has been determined as a function of absorber concentration w and equivalent pressure Pe for the major infrared absorption bands of carbon dioxide with centers at 3716, 3609, 2350, 1064, and 961 cm-1. The results in the 875-495 cm-1 region are expressed in terms of mean spectral absorptance Ā(ν1 − ν2) = ∫ ν1 ν2 A(ν)dν/(ν1 − ν2) for five separate subregions. The effects of temperature variations on absorption in some regions are discussed. Estimates of band intensity ∫ k(ν)dν are given for each band and are compared with the results of others.
Darrell E. Burch, David A. Gryvnak, and Dudley Williams, "Total Absorptance of Carbon Dioxide in the Infrared," Appl. Opt. 1, 759-765 (1962)