Potential Parameters and Energy Dependence of Rotational Energy Transfer in Molecular Systems

The cross-sections for rotational transitions in a diatomic molecule due to collision with an atom were computed. An empirical relation is obtained that gives the dependence of cross-sections on the energy of the colliding system and the parameters of the interaction potential energy surface. The results are interpreted to investigate the mechanism of the rotational energy transfer process. The cross-sections are found to depend linearly on the torque, range of the potential, and the collision time. Depending on the variation in the location of classical turning point with change in energy, the cross-sections may increase or decrease with energy or cross-section versus energy curve may exhibit maxima or minima.