Effects of reactant internal excitation and orientation on dissociative chemisorption of H2O on Cu(111): Quasi-seven-dimensional quantum dynamics on a refined potential energy surface.

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 H2O 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 H2O was investigated. It is shown that even low rotational excitation in H2O can either enhance or inhibit the reaction and the reactivity depends on the orientation of the impinging molecule. [ABSTRACT FROM AUTHOR]