Imaging CO2 Photodissociation at 157 nm: State-to-State Correlations between CO(v) and O(3Pj=0,1,2)

The spin forbidden CO(v) + O(P-3(j)) channel produced by 157 nm photodissociation of CO2 was investigated by velocity map imaging O(P-3) images were measured for the three P-3(j) spin-orbit states (j = 0, 1, and 2), and the CO vibrational-state distributions that correlate to the O(P-3(j=0,1,2)) spin-orbit product were determined. Nearly all energetically allowed product CO(v) levels (i.e., v <= 8) are observed with minor differences in the CO vibrational distributions for the three channels. The angluar anisotropy, which also shows minor differences for the three j channels is found to decrease with increasing CO vibrational excitation suggesting that the lower vibrational states are produced by photodissociation from a more linear OCO geometry. Fits to the total kinetic energy distributions suggest that the CO rotational energy is relatively cold. The overall results further suggest that the three spin-orbit pathways are not mixed completely in the exit channel.