Use este identificador para citar o ir al link de este elemento: http://hdl.handle.net/1843/61418
Tipo: Artigo de Periódico
Título: Synthesis and characterisation of the vibrational and electrical properties of antiferromagnetic 6l-ba2coteo6 ceramics
Autor(es): Anees Abdul Aziz
Silvana Mercone
Ricardo P. S. M. Lobo
Anderson Dias
Roberto Luiz Moreira
Anthony Martin Thomas Bell
Roger Eccleston
Antonio Feteira
Resumen: Optimal processing conditions for fabrication of dense single-phase 6L-Ba2CoTeO6 ceramics via the solid-state reaction method were determined. These ceramics possess a room-temperature crystal structure described by the centrosymmetric P[3 with combining macron]m1 space group. Polarized Raman spectroscopy enabled the observation of all the 25 predicted Raman modes and assignment of their symmetries. On cooling, BCTO ceramics exhibit two antiferromagnetic transitions at 3 K and 12.5 K, in broad agreement with a recent single-crystal study [P. Chanlert, N. Kurita, H. Tanaka, D. Goto, A. Matsuo and K. Kindo, Phys. Rev. B: Condens. Matter Mater. Phys., 2016, 93, 094420]. Low temperature Fourier-transform infrared reflectivity analyses suggest the antiferromagnetic phase transitions to be driven by small distortions of the CoO6 octahedra, lowering locally their C3v symmetry. This causes splitting of the associated vibrational modes, but without a long-range structural change. AC impedance spectroscopy revealed BCTO ceramics to be leaky insulators with an activation energy for conduction of ∼0.15−0.25 eV, which suggests electron hopping between mixed oxidation states of Co.
Asunto: Material cerâmico
Eletrônica do estado sólido
Raman, Espectroscopia de
Antiferromagnetismo
Fourier, Espectroscopia de infravermelho por transformada de
Oxidação
Idioma: eng
País: Brasil
Editor: Universidade Federal de Minas Gerais
Sigla da Institución: UFMG
Departamento: ICX - DEPARTAMENTO DE QUÍMICA
Tipo de acceso: Acesso Restrito
Identificador DOI: https://doi.org/10.1039/C9DT00418A
URI: http://hdl.handle.net/1843/61418
Fecha del documento: 2019
metadata.dc.url.externa: https://pubs.rsc.org/en/content/articlelanding/2019/dt/c9dt00418a#!
metadata.dc.relation.ispartof: Dalton Transactions
Aparece en las colecciones:Artigo de Periódico

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