COLLISION-INDUCED DISSOCIATION OF CO2+ IONS

Collision-induced dissociation experiments have been conducted on CO2 ions using three types of ion sources, different collision energies, light and heavy targets, and three different apparatuses possessing di fferent values of energy and angular resolution. Results of all these collision experiments establish that collision-induced dissociation dy namics is remarkably different from that obtained in photoionization e xperiments. Although the O+ + CO channel is the energetically lowest d issociation pathway, dissociation into CO+ + O is found to be the pref erred channel. Our measurements of the ratio CO+ to O+ are substantial ly higher than that obtained in photoionization experiments. Determina tions of kinetic energies released upon dissociation of CO2+ are also made. Rationalization of our results is attempted in terms of curve cr ossings of low-lying excited states of CO2+ ions. [S1050-2947(98)13109 -8].