Synthesis, crystal and magnetic structure of a novel brownmillerite-type compound Ca{sub 2}Co{sub 1.6}Ga{sub 0.4}O{sub 5}
- Department of Chemistry, Moscow State University, 119899 Moscow (Russian Federation)
- Department of Materials Chemistry, Moscow State University, 119899 Moscow (Russian Federation)
- Department of Structural Chemistry, Stockholm University, SE-10691 Stockholm (Sweden)
The novel compound Ca{sub 2}Co{sub 1.6}Ga{sub 0.4}O{sub 5} with brownmillerite (BM) structure has been prepared from citrates at 950{sup o}C. The crystal structure of Ca{sub 2}Co{sub 1.6}Ga{sub 0.4}O{sub 5} was refined, from neutron powder diffraction (NPD) data, in space group Pnma, a=5.3022(6)A, b=14.884(2)A, c=5.5276(6)A, {chi}2=1.798, RF2=0.0455, Rwp=0.0378 and Rp=0.0292. On the basis of the NPD refinement the compound was found to be a G-type antiferromagnet (space group Pn'm'a) at room temperature, with the magnetic moments of cobalt atoms directed along chains of tetrahedra in the BM structure. Electron diffraction and electron microscopy studies revealed disorder in the crystallites, which can be interpreted as the presence of slabs with BM-type structure of Pnma and I2mb symmetry.
- OSTI ID:
- 20658204
- Journal Information:
- Journal of Solid State Chemistry, Vol. 177, Issue 11; Other Information: DOI: 10.1016/j.jssc.2004.08.018; PII: S0022-4596(04)00458-X; Copyright (c) 2004 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
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