Collision-induced absorption by D2 pairs in the first overtone band at 77, 201 and 298 K

Abstract

Collision induced absorption (CIA) spectra of pure D2 in the first overtone region from 5250 to 7250 \(\mbox{cm}^{-1}\), recorded at 77, 201 and 298 K, have been analyzed. The observed spectra at 77, 201 and 298 K were modelled by a total of 92, 214 and 267 components respectively of double vibrational transitions at room temperature of the type X2(J)+X0(J) and X1(J)+X1(J), where X is O, Q or S transitions. Profile analyses of the spectra were carried out using the Birnbaum-Cohen line-shape function for the individual components of the band, and characteristic line shape parameters were determined from the analysis. The observed and calculated profiles agree well over the whole overtone band, and the agreement is better than 97% in the three cases studied. Binary and ternary absorption coefficients were determined from the integrated absorption of the band.