Mutual vibrational quenching in CO+H2 collisions

Vibrational quenching of CO and H2 is studied quantum mechanically for collisions where both molecules are vibrationally excited. A five-dimensional (5D) coupled states (CS) approximation is used to formulate the dynamics. The approximation is tested against six-dimensional (6D) results for CO+H2 with single vibrational excitation using both the CS approximation and the full close-coupling (CC) method. The 5D approximation is shown to provide a …