Structural studies on decagonal quasicrystals using the HAADF-STEM and CBED methods

The applications of the high-angle annular dark-field scanning transmission electron microscope (HAADF-STEM) and convergent-beam electron diffraction (CBED) methods to decagonal quasicrystals and its approximant are presented by giving some examples. The HAADF method can show the atomic arrangement mainly composed of transition metal (TM) atoms in Al-TM systems. The CBED method can determine the super point- and space-groups of quasicrystals, and furthermore can be used to refine the structural parameters.