Nonadiabatic small polarons, positive magnetoresistance, and ferrimagnetism behavior in the partially inverse Mn2-xV1+xO4 spinels

We present experimental results of electrical resistivity (ρ), magnetoresistance (MR), Seebeck coefficient (S), and magnetic susceptibility () experiments at high temperature on the spinel Mn2-xV 1+xO4 series with x=0, 1/ 3, and 1, prepared by solid state reaction. The Rietveld analysis of neutron p...

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Detalles Bibliográficos
Autores: Pannunzio Miner, Elisa Victoria, de Paoli, Juan Martin, Carbonio, Raul Ernesto, Sanchez, Rodolfo Daniel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/68573
Acceso en línea:http://hdl.handle.net/11336/68573
Access Level:acceso abierto
Palabra clave:geometrically frustrated
spinel
electric properties
magnetism
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:We present experimental results of electrical resistivity (ρ), magnetoresistance (MR), Seebeck coefficient (S), and magnetic susceptibility () experiments at high temperature on the spinel Mn2-xV 1+xO4 series with x=0, 1/ 3, and 1, prepared by solid state reaction. The Rietveld analysis of neutron powder diffraction (NPD) patterns confirm the expected cubic symmetry (SG: Fd-3m) with cell parameters around 8.5 Å. We also precisely calculate the distribution of Mn/V cations, in the tetrahedral and octahedral sites, for the whole series showing an important degree of inversion. The magnetic susceptibility and electrical transport properties show ferrimagnetic and semiconductor behaviors, respectively. A large difference detected between the activation energies for S and ρ indicates the presence of small polarons and the temperature dependence of ρ is well fitted with the nonadiabatic polarons model. All the samples present positive MR at room temperature, in particular, the highest value (around 1%) was observed in the MnV2O4 sample.