A LEED fine structure study of oxygen adsorption on Cu(001) and Cu(111)

LEED fine structure features are due to an interference between the measured beam (usually the specular) and a pre-emergent beam. This pre-emergent beam is internally reflected at the surface potential barrier and is subsequently diffracted by the substrate into the same direction as the beam under observation. As a result of the long-range image nature of the barrier potential, a rydberg-like series of peaks, converging on the emergence energy of the pre-emergent beam, is produced. Fine structure features, or threshold effects, occur at very low incident beam energies (typically