THEORETICAL-STUDY OF THE COLLISION-INDUCED FUNDAMENTAL ABSORPTION-SPECTRA OF N2-N2 PAIRS FOR TEMPERATURES BETWEEN 77-K AND 297-K

A procedure is presented for the analysis of the collision-induced fun damental absorption of pairs of N2 molecules on the basis of quantum l ineshapes computed from an accurate isotropic potential and multipole- induced dipole functions up to the hexadecapole term. The lineshape pa rameters were those obtained by Borysow and Frommhold from quantum com putations of the far infrared collision-induced absorption of N2. Beca use most of the other parameters appearing in the theoretical models f or the various induced dipole-moment components are now known from ind ependent measurements with reasonable accuracy, we compare the theoret ical results for the absorption, calculated without the introduction o f adjustable parameters, to the recent experimental results. We conclu de that although the overall agreement for all the temperatures consid ered is good, small systematic differences especially in the wings of the band remain. These differences can be reduced somewhat by varying the magnitudes of the input data but not completely reconciled. Severa l additional mechanisms that can affect the wings of the band are disc ussed briefly.