Enantiomorph identification of transition-metal disilicides with the C40 structure (the space group of P6{sub 2}22 and P6{sub 4}22) by new convergent-beam electron diffraction method

Journal Article · Mon Jan 03 04:00:00 EST 2005 · Acta Materialia

DOI:https://doi.org/10.1016/j.actamat.2004.08.001· OSTI ID:20637105

Sakamoto, Hiroki ^[1]; Fujii, Akihiro ^[1]; Tanaka, Katsushi ^[2]; Inui, Haruyuki ^[1]

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1. Department of Materials Science and Engineering, Kyoto University Sakyo-ku, Kyoto 606-8501 (Japan)
2. Department of Advanced Materials Science, Kagawa University, 2217-20 Hayashi-cho, Takamatsu, Kagawa 761-0396 (Japan)

The new CBED method we proposed recently for enantiomorph identification has been applied to transition-metal disilicides with the C40 structure (the space groups of P6{sub 2}22 and P6{sub 4}22). The enantiomorph can be easily identified by simply inspecting the intensity asymmetry of Bijvoet pairs of ZOLZ and/or FOLZ reflections in a CBED pattern taken along an appropriate zone-axis orientation. The way for enantiomorph identification with the present method is altered neither with the changes in the lattice parameters and averaged atomic scattering factors in the range expected for real C40 disilicide crystals of multi-component nor with the atom position parameter for Si atoms in 6j sites. The method is successfully applied to real C40 disilicides, and our single crystals of VSi{sub 2}, CrSi{sub 2}, TaSi{sub 2} and Mo(Si{sub 0.85}Al{sub 0.15}){sub 2} are determined to belong to P6{sub 4}22 whereas that of NbSi{sub 2} is determined to belong to P6{sub 2}22. These results are all consistent with those of our previous X-ray diffraction study.

• OSTI ID: 20637105
• Journal Information: Acta Materialia, Journal Name: Acta Materialia Journal Issue: 1 Vol. 53; ISSN 1359-6454; ISSN ACMAFD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHROMIUM SILICIDES
ELECTRON BEAMS
ELECTRON DIFFRACTION
ENANTIOMORPHS
HEXAGONAL LATTICES
LATTICE PARAMETERS
MOLYBDENUM SILICIDES
ORIENTATION
SILICIDES
SPACE GROUPS
TANTALUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
VANADIUM SILICIDES
X-RAY DIFFRACTION