Crystal structures and cation ordering of Sr2AlSbO6 and Sr2CoSbO6 |
| |
Authors: | A. Faik J.M. Igartua J.L. Pizarro R. Kaindl |
| |
Affiliation: | a Fisika Aplikatua II Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea, P.O. Box 644, Bilbao 48080, Spain b Australian Nuclear Science and Technology Organization, Private Mail Bag 1, Menai, NSW 2234, Australia c Departamento de Mineralogía y Petrología, Facultad de Ciencia y Tecnología, UPV/EHU, PB 644, Bilbao 48080, Spain d Departamento de Química Inorgánica, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain e Institute of Mineralogy and Petrology, University of Innsbruck, A-6020 Innsbruck, Austria f Departamento de Física de la Materia Condensada, Facultad de Ciencia y Tecnología, UPV/EHU, PB 644, Bilbao 48080, Spain |
| |
Abstract: | The two double perovskite oxides Sr2AlSbO6 and Sr2CoSbO6 were prepared and their structures studied with the X-ray powder diffraction method. At room temperature the crystal structure of Sr2AlSbO6 is cubic , with . It was found that depending on the preparation conditions, the Al3+ and Sb5+ cations can be either entirely or partially ordered. In the case of the partially ordered Sr2AlSbO6 sample, the extension of cation ordering was estimated from the -dependent broadening of the diffraction peaks and the results were interpreted as evidence of the formation of anti-phase domains in the material. Low-temperature Raman spectroscopic measurements demonstrated that the cubic phase of Sr2AlSbO6 is stable down to 79 K.The room-temperature crystal structure of Sr2CoSbO6 is trigonal (space group with and . At 470 K, however, the material undergoes a continuous phase transition and its structure is converted to cubic (space group . The studied Sr2CoSbO6 sample was partially ordered, but unlike Sr2AlSbO6, no indication of the formation of anti-phase domains was observed. |
| |
Keywords: | 61.10.Nz 61.50.Ks 61.66.Fu 64.70.Kb |
本文献已被 ScienceDirect 等数据库收录! |
|