Energy transfer in collisions of Ar with highly excited water and methane

Classical trajectories are used to study energy transfer in collisions of argon with water and methane molecules which initially contain 100 kcal/mol of vibrational energy. Energy transfer is investigated at different impact parameters, relative translational energies, and molecular rotational energies. Increasing the initial molecular rotational energy enhances both intermolecular energy transfer and collision-induced intramolecular vibrational ↔ rotational energy transfer. Of these two energy-transfer processes, the latter is found to be the more efficient.