Resonance formation of hydrogenic levels in front of metal surfaces

Abstract

The electronic self-energy of hydrogenic ions interacting with a jellium metal surface is studied within the fixed-ion approximation. A model framework is introduced that allows for the efficient computation of the complex ͑non-Hermitian͒ self-energy matrix in a large space of ͑bound͒ hydrogenic states. For the specific case of protons interacting with an aluminum surface, resonance energies and widths of dressed ionic states are obtained by diagonalizing the self-energy matrix. The hybridization properties of the dressed ionic states are analyzed. The self-energy of individual dressed states is found to converge rapidly with increasing dimension of the space of unperturbed hydrogen states. The resonance energies are compared to ͑1͒ energies obtained by diagonalizing only the direct couplings among the hydrogen states and ͑2͒ the real part of the diabatic ͑diag-onal͒ self-energy. This comparison demonstrates the pronounced effect that indirect couplings between hydrogen states via conduction band states have on the resonance energies at intermediate and small ion-surface distances. Our results for incident protons are confronted with the results of other ͑perturbative and nonper-turbative͒ calculations of level shifts and widths in proton-surface interactions. Although we use a simplified electronic potential, we find good agreement with calculations employing more refined potentials.

Wave packet propagation study of the charge transfer interaction in the F−–Cu(111) and –Ag(111) systems

“…Since the initial state |Ψ(t = 0) = |Ψ F − is orthogonal to the vector |Q , i.e., it is in the physical subspace, we can omit the projection operators to the left and right of the exponential in (11). So in (11) we take…”

“…Since a few years the development of accurate theoretical approaches to the RCT in the case of free electron metal surfaces [5][6][7][8][9][10][11] has led to a successful description of a one-electron transfer in the interaction of ions (atoms) with such surfaces [12][13][14]. All these approaches are based on the description of single electron being transferred between the atom and the surface.…”

H−formation in collisions of hydrogen atoms with Al(100) surfaces

“…For the particular case of H − interacting with Cu(111) metal surfaces, which support an L-band gap, it was demonstrated that for long ion-surface interaction times the active electron has enough time to respond sensitively to details of the substrate electronic structure and that the electronic dynamics of the collision system evolves adiabatically, consistent with the fixed-ion approximation [6][7][8]. In contrast, for short interaction times, details of the substrate electronic structure are not resolved, and the time evolution of the collision system is well described by a structureless jellium model for the target electronic distribution [9].…”

Auger neutralization and ionization processes for charge exchange between slow noble gas atoms and solid surfaces

“…1). Resonant processes, being one-electron ones, have been described abundantly in the literature, practically for any atom/solid combination, using different techniques [8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38].…”