Surface structure analysis by transmission electron diffraction: effects of the phases of structure factors

Abstract

To solve the problems related to the phases of the structure factors in surface structure analysis by transmission electron diffraction, the dynamical diffraction in the bulk crystal underneath the surface layer is considered by the many-beam theory. In the case of normal beam incidence, the intensities of superlattice reflections from surfaces and/or adsorbed layers are used to discriminate whether the surface structure is substitutional or displacive in type. In the case where only two beams are strongly excited in the bulk crystal, the phases of the structure factors of the surface layer are determined by the rocking curve of the superlattice reflections.