CO2 Vibrational State Distributions From Quasi-Classical Trajectory Studies of the HO plus CO → H + CO2 Reaction and H + CO2 Inelastic Collision

Quasi-classical trajectory studies have been carried out for the HO + CO -> H + CO2 reaction and H + CO2 inelastic collision on a recently developed global potential energy surface based on a large number of high-level ab initio points. The CO2 vibrational state distributions for these processes have been determined using an original normal-mode analysis method. It was found that the CO2 product of the reaction is highly excited in both the Fermi-linked bending and symmetric stretching modes, but little population was found in the antisymmetric stretching mode. The substantial excitation of the CO2 vibration, while consistent with the geometry of the transition state in the exit channel, is in disagreement with available experimental data. For the inelastic collision, the CO2 is much less excited despite much higher total energies. In addition, excitations in all vibrational modes were found, in good agreement with experiment.