Chemical substitution of surface atoms in structure determination by tensor low-energy electron diffraction

Abstract

We present a chemical perturbation method for surface-structure determination by low-energy electron diffraction (LEED). It is based on tensor LEED theory and is able to substitute selected surface atoms by other chemical species making full dynamical calculations for the structure unnecessary. The potential of the approach is demonstrated for the determination of the surface stoichiometry of substitutionally disordered alloys, for the switching from one adsorbate species to another, and for the generation of superstructures by substitution of surface atoms by vacancies.