Oxidation products of Nb{sub 4}W{sub 13}O{sub 47}: A transmission electron miscroscopy study
- Universitat Bonn, Romerstrasse (Germany)
- Universitat Gieben, Giessen (Germany)
Nb{sub 4}W{sub 13}O{sub 47}, a mixed valency oxide crystallizing in the structure of the 4:9 phase (4Nb{sub 2}O{sub 5}.9WO{sub 3}), was oxidized at various temperatures. The products have been characterized by high-resolution transmission electron microscopy. Oxidation products obtained at 600 and 1000{degrees}C exhibit the development of planar defects running along (110) of the TTB subcell. The defects built up by structural elements observed here for the first time: Two or more five-membered rings of octahedra are connected via two common octahedra. These arrays are combined with blocks of ReO{sub 3}-type structure and ordered along the defect planes. The oxidation at 1200{degrees}C leads to a separation into the 2:7 phase and WO{sub 3}.
- OSTI ID:
- 283007
- Journal Information:
- Journal of Solid State Chemistry, Vol. 120, Issue 2; Other Information: PBD: Dec 1995
- Country of Publication:
- United States
- Language:
- English
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