Effects of reactant internal excitation and orientation on dissociative chemisorption of H_2O on Cu(111): Quasi-seven-dimensional quantum dynamics on a refined potential energy surface

摘要

To understand the influence of reactant internal excitation and orientation on the dissociative chemisorption of water on Cu(111), a quasi-seven- dimensional quantum dynamics study has been carried out on a refined potential energy surface (PES). The new PES was modified in the asymptotic region to allow an accurate characterization of the H_2O ro-vibrational levels. The mode selectivity of the reaction was reexamined on the new PES and found to be consistent with our earlier work. To rationalize the observed mode selectivity, a vibrationally adiabatic reaction path model was determined on this PES. Furthermore, the reactivity for various rotationally excited H_2O was investigated. It is shown that even low rotational excitation in H_2O can either enhance or inhibit the reaction and the reactivity depends on the orientation of the impinging molecule.