Low-Energy Electron Diffraction Study of the Cleaved Surfaces of PbS, PbSe, and PbTe

Abstract

Low‐energy electron diffraction was used to study the cleaved surfaces of PbS, PbSe, and PbTe for the purpose of obtaining information about the factors that influence the intensities of the diffracted beams. The addition of the successively heavier anion in the three compounds produced no significant changes in the intensities that could be attributed to the atomic scattering factors of the anions. Prominent features in the dependence of the intensity of the diffracted beams on the energy of the incident electrons are attributed to multiple scattering. The structure of the surfaces in two dimensions parallel to the surface is the same as the (001) substrate planes. A complete analysis of structure normal to the surface is prevented by strong multiple scattering. Single scattering events are identified at low energies by measurements on the angular dependence of the intensities.