ANGULAR DISTRIBUTIONS FOR PHOTODISSOCIATION OF O2 IN THE HERZBERG CONTINUUM

Photodissociation in the Herzberg continuum of molecular oxygen has been studied at 236, 226 and 204 nm. Using ion-imaging and monitoring of O(3Pj), j=0, 1, and 2 product-atom angular distributions, the amount of parallel character of the transition was measured. In order to interpret these data, analyses of the photoabsorption oscillator strengths and the parallel-perpendicular nature of the Herzberg I, II and III bands, and extrapolation of these properties into the Herzberg-continuum region have been performed. Our measured fine-structure-averaged angular distributions are found to be consistent with this photoabsorption model. In addition, the dynamics of the dissociation process is discussed, based on the O-atom fine-structure distributions.

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