Statehyphen;tohyphen;state vibrational predissociation of H2ndash;HF and D2ndash;HF. Direct comparisons between theory and experiment

摘要

The optothermal detection method has been used to measure photofragment angular distributions resulting from the vibrational predissociation of both H2ndash;HF and D2ndash;HF. These angular distributions show resolvable structure which can be related to the final rotational state distributions, including the scalar intermolecular rotational correlations. H2ndash;HF dissociates via a predominantlyVndash;Rprocess, while in D2ndash;HF the open D2vibrational channel is the main depository for the excess energy. The experimental results are compared directly with the recent timehyphen;independent closehyphen;coupling calculations of Clary lsqb;J. Chem. Phys.96, 90 (1992)rsqb; and the timehyphen;dependent golden rule calculations of Zhang, Zhang, and Baccaron;icacute; lsqb;J. Chem. Phys.97, 927; 3149 (1992); Chem. Phys. Lett.194, 313 (1992)rsqb;. The fact that these two systems have very different dynamics, while the potentialhyphen;energy surfaces are the same, is particularly useful in providing new insights into the nature of the coupling responsible for predissociation.