The Infrared Absorption Spectrum of Carbon Dioxide

Abstract
The complete infrared spectrum of CO2 may consistently be explained in terms of a linear symmetrical model, making use of the selection rules developed by Dennison and the resonance interaction introduced by Fermi. The inactive fundamental ν1 appears only in combination bands, but ν2 at 15μ and ν3 at 4.3μ absorb intensely.