Quantum dynamics of H-2-surface scattering: H-2+LiF(001) and H-2+Cu(100)

We consider the scattering of H-2 from surfaces for two benchmark systems. The system H-2 + LiF(001) is the classical example of hydrogen scattering o ff an ionic surface. Quantum dynamical calculations employing a new model p otential and experiments have shown that the electrostatic interaction betw een the molecule's quadrupole moment and the surface ions has a crucial inf luence on the scattering in this system. The results suggest that the ionic ity of the surface ions in ionic surfaces can be probed by scattering H-2 O f these surfaces, for instance, by measuring the differences between diffra ction of cold p-H-2 and cold o-H-2. The system H-2 + Cu is the classic exam ple of activated dissociative chemisorption. It is now possible to perform quantum dynamical calculations on fully activated dissociative chemisorptio n in which all molecular degrees of freedom are treated without dynamical a pproximations, as here illustrated for H-2 + Cu(100). This development make s it possible to evaluate the accuracy of electronic structure methods for molecule-surface interactions, to help interpret trends in the reactivity o bserved experimentally, and to arrive at new predictions for experiments.