In recent years a number of resonance-enhanced mechanisms and focusing effects have been reported in inelastic atom-surface scattering. In this paper, we show that most of such scattering singularities are due to large values of the Jacobian (or density of states) of the incident momentum with respect to the final scattering angle leading to a unified theoretical scheme for their treatments. As a result, focused resonance-enhanced mechanisms are proposed and analyzed in order to improve the detection of bound states of low-index metal surfaces.

• Received 10 December 1998

DOI:https://doi.org/10.1103/PhysRevB.60.1547