High-Resolution Electron Microscopy of Quasicrystals

Abstract

I review the current results of our group of a high-resolution electron microscopy study of the icosahedral quasicrystal, by using 200 kV and 400 kV electron microscopes which have resolutions of 0.23 and 0.17 nm, respectively. High-resolution lattice images, taken with the 200 kV microscope, clearly show topologjcal features of quasicrystalline lattices which are in good agreement with the Penrose lattices, and also reveal interesting defects, such as quenched phason strains and dislocations. High-resolution structure images taken with the 400 kV microscope show that the atomic arrangements of the icosahedral quasicrystals are formed by closely packing aggregations of atom clusters with icosahedral symmetry.