9319436 Rous A comprehensive theoretical description of resonance electron scattering by molecules adsorbed on solid surfaces will be developed and applied to understand the fundamental physics of negative ion formation at surfaces. The computational methodology will be based upon the layer-Kohn-Korringa-Rostoker theory which will fully incorporate the multiple scattering of the trapped electron by the substrate and surface barrier. Thus the influence of the unoccupied electronic structure of the substrate on the molecular resonance will be modelled. The dependence of resonance lifetime and energy upon the molecular adsorption height (above the surface), adsorption site and molecular orientation will be explored in order to elucidate the link between the adsorption geometry of a molecule and the behavior of the transient (resonance) state. %%% In a variety of electron and photon stimulated surface dynamical processes, short lived "resonance" electronic states localized mainly upon the adsorbed molecule are known to be important. The proposed work concerns itself with characterizing both the energy of these states and their lifetime via computationally intensive methodologies. The work will concentrate on how the presence of the nearby surface affects the resonance states of the free-space molecule and, further, how these states vary as a function of the location and orientation of the molecule relative to the surface. ***
