Theoretical study of the photodissociation cross sections and the photodissociation dynamics of hypochlorous acid

Abstract

Potential energy surfaces for electronic ground and excited states of HOCl, which are related to the experimentally observed photoabsorption between 400 and 200 nm, were calculated with the ab initio molecular orbital (MO) configuration interaction (CI) method. The transition dipole moment surfaces between these states were also calculated. Two types of model calculations were carried out for evaluation of the theoretical photodissociation cross section. Theoretical spectra exhibit two peaks at about 335 and 245 nm. They are in better agreement with the experimental results than those in the previous study. The present calculation supports the assumption that the HOCl molecule in the stratosphere may contribute to ozone depletion. The rotational state distributions of the product OH({sup 2}II) were explored with classical trajectory calculations. The rotational state distributions are dependent on the excited state. 36 refs., 14 figs., 3 tabs.