ELECTRONIC CONTROL OF THE SPIN-ORBIT BRANCHING RATIO IN THE PHOTODISSOCIATION AND PREDISSOCIATION OF HCL

The fine structure branching ratio of chlorine atoms produced in the photodissociation and predissociation of HCl was measured for excitation energies between 51 800 and 83 800 cm(-1). The branching ratio between 60 000 and 70 000 cm(-1) is in good agreement with the calculations of Alexander et al. [J. Chem. Phys, 99, 1752 (1993)], converging to the statistical limit at high energy. Predissociation of electronically excited bound states display a surprisingly rich behavior, demonstrating that the nature of the predissociating continuum state has a large effect on the atom fragment branching ratio. (C) 1995 American Institute of Physics.