Quenching of infrared chemiluminescence. Part 4.—Rates of energy transfer from CO(4 ⩽v⩽ 12) to diatomic hydrides and deuterides

Abstract

Results are reported from an experimental study of the quenching of the infrared chemiluminescence from vibrationally excited CO, formed in the reaction O(³P)+ CS → CO + S, by HCl, DCl, HBr, DBr, normal-H₂, and para-H₂. Rates are obtained for V–V energy exchange from CO(4 ⩽v⩽ 12) to DCl and DBr. The variation of these rates with ν, and hence with Δν, the difference between the vibrational transition energies in the two molecules, indicates that some of this energy discrepancy can be absorbed as rotational energy by the deuteride. No differences between the quenching by n–H₂ and p–H₂ could be distinguished. The possible mechanisms for transfer of energy between CO and H₂ are discussed and the results of theoretical calculations on near-resonant V–R energy transfer and V–V energy exchange are presented.