Structural, magnetic, and electrical properties of Bi1-xLaxMnO3 (x=0.0, 0.1, and 0.2) solid solutions
Abstract
Possible ferromagnetic and ferroelectric orders in ceramic Bi1–xLaxMnO3 (x = 0.0, 0.1, and 0.2) samples prepared under 3–6 GPa pressure have been investigated. Rietveld fits to powder neutron diffraction data show that BiMnO3 and Bi0.9La0.1MnO3 adopt a monoclinic C2/c perovskite superstructure whereas Bi0.8La0.2MnO3 has orthorhombic Pnma symmetry. Both structural analysis and Curie–Weiss fits to magnetic susceptibility data show that high spin d4 Mn3+ is present with no significant Bi deficiency or Mn4+ content apparent. La substitution suppresses the magnetic Curie temperature of the monoclinic phase from 105 K for x = 0 to 94 K at x = 0.1, but the x = 0.2 material shows antiferromagnetic order similar to that of LaMnO3. Impedance spectroscopy and dielectric measurements on the x = 0.1 and 0.2 materials show modest bulk permittivity values (45–80) down to 50 K, and there is no strong evidence for ferroelectric behavior. The two samples have thermally activated conductivities with activation energies of 0.21–0.24 eV.
Citation
Chen , W-T , Sher , F , Mathur , N D , Kavanagh , C M , Morrison , F D & Attfield , J P 2012 , ' Structural, magnetic, and electrical properties of Bi 1-x La x MnO 3 (x=0.0, 0.1, and 0.2) solid solutions ' , Chemistry of Materials , vol. 24 , no. 1 , pp. 199-208 . https://doi.org/10.1021/cm202900v
Publication
Chemistry of Materials
Status
Peer reviewed
ISSN
0897-4756Type
Journal article
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