Coexistence of localized and itinerant electrons in the novel double perovskite Ba2Fe2/3Mo4/3O6

Authors
Lopez, Carlos Alberto; Saleta, Martin Eduardo; Pedregosa, Jose Carmelo; Sanchez, Rodolfo Daniel; Alonso, José A.; Fernández Díaz, María T.
Publication Year
2014
Language
English
Format
article
Status
Published version
Description
A polycrystalline Ba2Fe2/3Mo4/3O6 double-perovskite has been prepared by decomposition of citrate precursors and subsequent thermal treatment under a reducing atmosphere. The crystal structure has been studied by combined X-ray and neutron powder diffraction (XRPD and NPD). At room temperature, the structure is cubic (Fm-3m) with lattice parameter a = 8.0710(1) Å. It is unchanged between 3 and 320 K. The crystallographic formula is Ba2[Fe0.52(2)Mo0.48(2)]4a[Fe0.14(2)Mo0.86(2)]4bO5.9(2). NPD, electron spin resonance (ESR), and magnetization measurements show spontaneous magnetization below the Curie temperature (TC) = 310 K. The ESR behavior is associated with the presence of localized Fe3+ ions, whereas the transport properties (electrical conductivity and Seebeck effect) suggest the presence of highly correlated electrons in a metallic band with disorder, which can be associated with the Mo t2g electrons. The coexistence of localized and itinerant electrons leads to non-negligible magnetoresistance properties.
Fil: Lopez, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Investigaciones En Tecnología Química; Argentina
Fil: Saleta, Martin Eduardo. Comision Nacional de Energi­a Atomica. Gerencia del Area de Investigaciones y Aplicaciones no Nucleares. Gerencia de Fisica (CAB); Argentina
Fil: Pedregosa, Jose Carmelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Investigaciones En Tecnología Química; Argentina
Fil: Sanchez, Rodolfo Daniel. Comision Nacional de Energi­a Atomica. Gerencia del Area de Investigaciones y Aplicaciones no Nucleares. Gerencia de Fisica (CAB); Argentina
Fil: Alonso, José A.. Instituto de Ciencia de Materiales de Madrid; España
Fil: Fernández Díaz, María T.. Institut Laue Langevin; Francia
Subject
Ba3FeMo2O9
CMR
PEROVSKITE STRUCTURE
Fe/Mo ORDERING
HIGHLY CORRELATED ELECTRONS
TRANSPORT PROPERTIES
Química Inorgánica y Nuclear
Ciencias Químicas
CIENCIAS NATURALES Y EXACTAS
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/5846