Use of dynamic electron scattering for studying the position of oxygen atoms in simple metal oxide

Hrem Visualization of Light Atoms: An Application to the Study of Carbon Defects in Ordered Transition Metal Carbides

This paper gives an overview of recent High Resolution Electron Microscopy (HREM) observations of transition metal carbides. The main point is to show how HREM can be used to study a sublattice of light atoms within a complex crystal. General tendencies of this approach will be outlined, which appear, to a large extent, to be common to similar possible studies of other compounds such as nitrides, borides or oxides. Specifically, attention is focused on studies of long-range ordered structures in carbides, due to non-stoichiometry accommodated by metalloid vacancies. Various examples are given for representative compounds, including V8C7, V6C, 5, Nb6C5 and W2C.

High-resolution electron microscopy and domain structures of pentagonal Frank-Kasper phases

The Laboratory of Atomic Imaging of Solids is dedicated to the direct imaging of materials in various fields of solid-state sciences at the atomic or molecular level. The main programs of this laboratory are briefly described, including quasicrystals, new phases and microdomains in Frank-Kasper phases, suboxides of metals, catalysts, minerals found in China, and molecular structure of organic substances. A recent systematic investigation of domain structures consisting of juxtaposed icosahedral columns is also presented.