The interplay of microstructure and magnetism in La{sub 3}Ni{sub 2}SbO{sub 9}

Journal Article · Mon Dec 15 00:00:00 EST 2014 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/J.JSSC.2014.08.024· OSTI ID:22451125

Avdeev, Maxim ^[1]; Hadermann, Joke ^[2]

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1. Bragg Institute, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234 (Australia)
2. EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)

La{sub 3}Ni{sub 2}SbO{sub 9} adopts a perovskite-related structure in which the six-coordinate cation sites are occupied alternately by Ni{sup 2+} and a disordered arrangement of Ni{sup 2+}/Sb{sup 5+}. A polycrystalline sample has been studied by neutron diffraction in applied magnetic fields of 0≤H/kOe≤50 at 5 K. In 0 kOe, weak magnetic Bragg scattering consistent with the adoption of a G-type ferrimagnetic structure is observed; the ordered component of the magnetic moment was found to be 0.89(7) µ{sub B} per Ni{sup 2+} cation. This increased to 1.60(3) µ{sub B} in a field of 50 kOe. Transmission electron microscopy revealed variations in the Ni:Sb ratio across crystallites of the sample. It is proposed that these composition variations disrupt the magnetic superexchange interactions within the compound, leading to domain formation and a reduced average moment. The application of a magnetic field aligns the magnetisation vectors across the crystal and the average moment measured by neutron diffraction increases accordingly. The role played by variations in the local chemical composition in determining the magnetic properties invites comparison with the behaviour of relaxor ferroelectrics. - Graphical abstract: Composition variations across a crystal of La3Ni2SbO9 result in anomalous magnetic behavior. - Highlights: • Ordered magnetic moment of Ni{sup 2+} increases in an applied magnetic field. • Composition variations detected by electron microscopy. • Increase in magnetic moment can be explained by presence of composition variations.

• OSTI ID: 22451125
• Journal Information: Journal of Solid State Chemistry, Vol. 220; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ANTIMONY IONS
CATIONS
CHEMICAL COMPOSITION
COORDINATES
FERRIMAGNETISM
FERROELECTRIC MATERIALS
LANTHANUM COMPLEXES
MAGNETIC FIELDS
MAGNETIC MOMENTS
MAGNETIC PROPERTIES
MAGNETIZATION
MICROSTRUCTURE
NEUTRON DIFFRACTION
NICKEL IONS
PEROVSKITE
POLYCRYSTALS
TRANSMISSION ELECTRON MICROSCOPY