VIBRATIONAL-STATE DISTRIBUTION OF CO2 PRODUCED IN THE REACTION BETWEEN OH RADICALS AND CO

A tunable diode laser has been used to observe transient absorptions on transitions in the v3 infrared bands of CO2 when it is formed as a product of the flash-initiated reaction between OH and CO. The absence of any population in excited states with v3 > 0 and the limited extent of excitation in the Fermi-linked v1 and v2 modes indicate that energy is released largely as repulsion following passage through a transition state in which the OCO atoms are close to their final structure in isolated CO2.