New Fe3+/ Cr3+ Perovskites with Anomalous Transport Properties: The Solid Solution LaxBi1鈥?i>xFe0.5Cr0.5O3 (0.4

详细信息    查看全文

• 作者：M. E. Villafuerte-Castrejo虂n ; M. Garci虂a-Guaderrama ; L. Fuentes ; J. Prado-Gonjal ; A. M. Gonza虂lez ; M. A虂. de la Rubia ; M. Garci虂a-Herna虂ndez ; E. Mora虂n
• 刊名：Inorganic Chemistry
• 出版年：2011
• 出版时间：September 5, 2011
• 年：2011
• 卷：50
• 期：17
• 页码：8340-8347
• 全文大小：1035K
• 年卷期：v.50,no.17(September 5, 2011)
• ISSN：1520-510X

文摘

In this work, the sol鈥揼el synthesis, structural characterization, and transport properties of a new solid solution of the general formula La_xBi_1鈥?i>xFe_0.5Cr_0.5O₃ (0.4 鈮?x 鈮?1) are presented. The solubility limit x has been determined and variation of the lattice parameters measured through profile fitting. The cell parameters, space group, and atomic positions, as obtained by the Rietveld refinement of X-ray diffraction data, are reported. This analysis and electron diffraction studies as well do not reveal any evidence of Fe/Cr ordering. Regarding the transport properties, magnetic and electric characterizations are described. The electrical response with the temperature and frequency has been studied, and a 鈥減ositive temperature coefficient鈥?for the resistivity has been found for temperatures between 270 and 400 掳C. The magnetic behavior is striking because, for all materials studied, zero-field-cooling curves appear above field-cooling ones, an anomalous feature that is interpreted as being due to complex ferromagnetic/antiferromagnetic interactions in the B perovskite sublattice.