Ferrimagnetism and metal-insulator transitions in the LaMnxRu1-xO3 perovskites

Gonen, ZS and Gopalakrishnan, J and Eichhorn, BW (2002) Ferrimagnetism and metal-insulator transitions in the LaMnxRu1-xO3 perovskites. In: Solid State Sciences, 4 (6). pp. 773-778.

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Abstract

: We describe the synthesis, structure, magnetic and electrical properties of solid solutions of nominal composition, LaMnxRu1-xO3 (0 < x < 1). All the members crystallize in the GdFeO3-perovskite structure where Mn/Ru are randomly distributed at the octahedral sites. Weight losses due to hydrogen reduction, recorded using thermogravimetry, suggest considerable nonstoichiometry arising from partial oxidation of Mn/Ru to the tetravalent state. The nonstoichiometry is most likely accommodated by creating vacancies both at A and B sites of the perovskite structure, just as it occurs in LaMnO3+y. Members with x greater than or equal to 0.50 exhibit a short-range ferro/ferrimagnetic order below 150 K that is likely due to Mn-III/VI-O-Ru-III (ferrimagnetic) and Mn-III-O-Mn-VI (ferromagnetic) interactions in the perovskite structure. All the members are semiconducting including the x = 0.05 member, suggesting that a metal-insulator transition occurs in the LaMnxRu1-xO3 system for x less than or equal to 0.05.

Item Type:	Journal Article
Publication:	Solid State Sciences
Publisher:	Elsevier Science
Additional Information:	Copyright of this article belongs to Elsevier Science.
Keywords:	Defect Structure;Magnetic Order;Lamno3+Delta;Magnetoresistance;Sr; Ba;Ca.
Department/Centre:	Division of Chemical Sciences > Solid State & Structural Chemistry Unit
Date Deposited:	21 Jul 2009 10:13
Last Modified:	19 Sep 2010 05:01
URI:	http://eprints.iisc.ac.in/id/eprint/18375

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