High-resolution electron microscopy imaging of the carbon vacancy superlattice in the ordered carbide VC1−x
- 1 April 1989
- journal article
- research article
- Published by Taylor & Francis in Philosophical Magazine A
- Vol. 59 (4), 885-906
- https://doi.org/10.1080/01418618908209826
Abstract
High-resolution electron microscopy (HREM) has been applied to the study of the order-disorder phenomena in vanadium carbide VC1−x near the composition V6C5. HREM images have been obtained by collecting in the objective aperture superstructure spots associated with the ordered distributon of vacancies in the carbon sublattice. Direct interpretation of experimental micrographs can be done for particular imaging conditions which are determined in this work from multislice image computations. Applications of the direct lattice imaging technique to the study of order defects is illustrated by two examples: first, micrographs taken from as-grown VC∼0.84 crystals confirm the existence of the monoclinic cell proposed by Billingham et al.; secondly, HREM images allow Hiraga's model to be refined for long-period structures which can develop in crystals, showing departure from the exact V6C5 composition.Keywords
This publication has 17 references indexed in Scilit:
- A first HREM observation of the ordered carbon sublattice in a transition-metal carbide (VC1-x)Philosophical Magazine Letters, 1987
- Use of dynamic electron scattering for studying the position of oxygen atoms in simple metal oxideUltramicroscopy, 1986
- Direct Resolution and Identification of the Sublattices in Compound Semiconductors by High-Resolution Transmission Electron MicroscopyPhysical Review Letters, 1986
- Order-Disorder Phase Transition Channel in Niobium CarbidePhysica Status Solidi (a), 1986
- High-resolution studies of order and disorder in alloysUltramicroscopy, 1985
- Order and disorder in transition metal carbides and nitrides: experimental and theoretical aspectsPure and Applied Chemistry, 1985
- High-voltage, high-resolution electron microscopy of Au–Cd alloys. III. One-dimensional long-period superstructure ofDO23typeJournal of Applied Crystallography, 1981
- The preparation of single crystals of refractory carbides and nitridesJournal of Crystal Growth, 1981
- Vacancy ordering in vanadium carbides based on V6C5Philosophical Magazine, 1973
- A superlattice with monoclinic symmetry based on the compound V6C5Philosophical Magazine, 1972