Abstract
Atomic structural analysis methods for crystal surfaces by reflection high-energy positron diffraction are described with a dynamical diffraction theory for positron beams. Using the one-beam approximation method, surface normal components of atomic positions are determined easily. Subsequently surface lateral components are determined by a dynamical analysis of rocking curves at symmetrical incidence for a certain crystal axis and/or the analysis of intensity distribution of spots in diffraction patterns using the result of the one-beam analysis. For adsorbed surfaces, it is noted that it is easy to determine adsorption heights of adsorbates by a one-beam rocking curve at the total reflection region. As examples of surface structural analyses, methods of atomic structure determinations for the Si(111)√21×;√21-Ag and the Si(111)7×7 surface are described.
