Collision complex formation in the low-energy dynamics of the C+ + O2 reaction

A crossed beam study of CO⁺ production from the C⁺ + O₂ reaction at a collision energy of 0.57 eV is presented. Very clear collision complex dynamics are observed which are shown to be consistent with the decay of a transient complex having a lifetime of approximately 0.5 ps. An analysis of the reactive scattering using an adiabatic state correlation diagram indicates that the formation of X-state CO₂⁺ by insertion of C⁺ into the O₂ bond is accessible from the reagents and correlates adiabatically with ground-state products. The average kinetic energy release is approximately 23% of the available energy. A comparison of the present data with the chemiluminescent studies of A-state production of CO⁺ indicates that the dominant channels at low energies are production of ground-state CO⁺ through the X²Π_g and a⁴Π_u state of CO₂⁺.