PHOTODISSOCIATION OF OXYGEN MOLECULES AT 226 NM IN THE HERZBERG-I SYSTEM

Doppler profiles of O(2p 3P(j)) (j = 2,1,0) produced from the photodissociation of O2 in the Herzberg I system (A 3-SIGMA-u+ <-- X 3-SIGMA-g-) at 226 nm are measured with a resonance-enhanced multiphoton ionization technique. The anisotropy parameter for the angular distribution of the photofragments is found to be 1.6 +/- 0.4, in quantitative agreement with theory and indicating that the Herzberg I system borrows most of its intensity from a parallel band. The branching ratios to the j levels of O(2p 3P(j)) (j = 2,1,0) are found to be (2.5 +/- 0.3):1:(0.26 +/- 0.03) and are compared with the values expected for the limits of adiabatic and diabatic dissociation.