(V,T) collisional energy exchange in CO + H₂gaseous mixtures

The (V, T) energy exchange in collisions is theoretically examined over a wide range of temperatures for the CO-H2 system. A full potential energy surface (PES) previously computed via the Electron Gas Model (EGM), and which explicitly included bond changing effects, is employed within a coupled quantum treatment of the dynamics to yield vibrational excitation and de-excitation cross sections for both CO and H2 as targets. The importance of the coupling potential size and shape within the radial range of partners' interaction is examined and their effect on the energy transfer mechanism are discussed. Low temperature behaviour of the CO relaxation is compared with experiments and the possible role of a V-V transfer mechanism is analysed.