LINEAR PHOTOELECTRON DIFFRACTION - APPLICATION OF A RAPID APPROXIMATION FOR SURFACE STRUCTURAL STUDIES

The linear superposition approximation proposed by Wander, Pendry and Van Hove for efficient low-energy electron diffraction calculations (' 'linear LEED'') is applied to photoelectron diffraction (''linear PD'' ). As with linear LEED, linear PD works very well for calculating the effect of displaced atoms. However, due to strong forward scattering a t higher energies, linear PD requires that atoms do not move into or o ut of alignment. This limitation can be removed by suitable simple adj ustments to the basic approximation, promising to make the method effe ctive for structural searches of complex surfaces.