Reaction dynamics of O(D-1)+HD. II. Effects of excited surfaces

To explore the effects of excited surfaces on the title reaction, an in-dep th crossed-beam investigation was carried out at two collision energies, 3. 7 and 4.6 kcal/mol. In combination with the results obtained at the lower e nergy, 2.05 kcal/mol (the preceding paper), the extent of abstraction contr ibution to total reactivity was deduced from the doubly differential cross- section measurements and its dominant dynamical features were revealed for the first time. The former was found to be in reasonable agreement with our previous estimate based on the excitation function data. We also present q uasiclassical trajectory results based on accurate potential energy surface s for the 1 (1)A' and 1 (1)A " surfaces. The trajectory results give approx imately the same breakdown into insertion and abstraction components as in the experiments, and some aspects of the product distributions, such as the angular distributions, are in rough agreement. However, other aspects of t he product distributions, such as the abstraction component of the product translational distributions, are in serious disagreement. Possible deficien cies in the potential surfaces and dynamics that could be responsible for t hese results are considered. (C) 1999 American Institute of Physics. [S0021 -9606(99)00641-8].