COLLISION-INDUCED ABSORPTION IN DIATOMIC MOLECULE/RARE-GAS MIXTURES

Abstract : A quantum mechanical calculation is given for collision-induced absorption in the infrared and far-infrared spectral regions for mixtures consisting of symmetrical diatomic molecules and rare-gas atoms. The induced moment consists of a short-range overlap term and a long-range quadrupole term. Near molecular transition lines, the quadrupole term gives the main contribution to the absorption, while in the far wings, the overlap term is dominant. The H2-He, H2-Ar, N2-Ar systems are considered, and an estimate is given of the absorption coefficient near 10 millimicrons for N2-N2 systems.