title: Line-Mixing Effects in Q Branches of CO2
abstract: A theoretical model based on the energy corrected sudden (ECS) approximation is used in order to account for line-mixing effects in Delta left and right arrow Pi infrared Q branches of 12C16O2. Its quality is demonstrated by comparisons with numerous laboratory spectra of CO2-He and CO2-N2 mixtures: three Q branches in the 4 and 17 μm regions are investigated at room temperature in a wide pressure range. The influence of mixing between Q(J) lines associated with odd and even values of the rotational quantum number J is demonstrated and analyzed in detail. It is shown that, in contrast to available fitting law approaches, the ECS model correctly predicts the influence of the parity of the rotational quantum numbers J and J' on coupling between the Q(J) and Q(J') lines. Comparisons between the effects of collisions of CO2 with N2 and He are made and analyzed. They show that these two systems involve different line couplings within the Q branch. Copyright 1997 Academic Press. Copyright 1997Academic Press
authors.affiliation: Laboratoire de Physique Moleculaire et Applications, UPR 136 du CNRS, associee aux Universites P. et M. Curie et Paris-Sud, Universite Paris-Sud (bat. 350), Orsay Cedex, 91405, France
authors.initials: R
authors.lastname: Rodrigues
authors.initials: G
authors.lastname: Blanquet
authors.initials: J
authors.lastname: Walrand
authors.initials: B
authors.lastname: Khalil
authors.initials: RL
authors.lastname: Doucen
authors.initials: F
authors.lastname: Thibault
authors.initials: J
authors.lastname: Hartmann