UC Davis

Photodissociation of CO2 is investigated between 13.540 eV and 13.678 eV using the time-sliced velocity-mapped ion imaging (TSVMI) apparatus that is combined with one-color and two-color pump-probe VUV + VUV and VUV + UV detection schemes by probing oxygen fragments at different levels. Several CO2 dissociation channels are directly observed from the ion images, namely CO(X (1)Σ(+)) + O((1)D), CO(X (1)Σ(+)) + O((1)S), CO(a (3)Π) + O((3)P), CO(a (3)Π) + O((1)D), CO(a' (3)Σ(+)) + O((3)P), CO(d (3)Δ) + O((3)P) and CO(e (3)Σ(-)) + O((3)P), whereas no CO(X (1)Σ(+)) + O((3)P) production has been found. The product kinetic energy distributions of these channels are reported for the first time. Possible dissociation mechanisms have been discussed based upon the product vibrational and rotational distributions.