Structure and physical properties of YCoO{sub 3} at temperatures up to 1000 K

Journal Article · Thu Jun 01 04:00:00 EDT 2006 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.73.2· OSTI ID:20788209

Knizek, K; Jirak, Z; Hejtmanek, J; Veverka, M; Marysko, M ^[1]; Hauback, B C ^[2]; Fjellvaag, H ^[3]

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1. Institute of Physics ASCR, Cukrovarnicka 10, 162 53 Prague 6 (Czech Republic)
2. Institute for Energy Technology, NO-2027 Kjeller (Norway)
3. Department of Chemistry, Center for Materials Science and Nanotechnology, University of Oslo, Oslo (Norway)

The crystal structure of perovskite YCoO{sub 3} has been studied by neutron powder diffraction up to high temperatures. The orthorhombic Pbnm symmetry is confirmed in the whole temperature range. A significant isotropic enlargement of CoO{sub 6} octahedra is evidenced above 600 K leading to unit cell expansion and increased octahedral tilting. Supported by complementary physical measurements, the origin of anomalous expansion is identified with a gradual transition of Co{sup 3+} ions from the diamagnetic low-spin (S=0) ground state to excited magnetic states with spin S=1 or 2. The magnetic transition is closely followed by a broad resistivity transition of the insulator-metal type, centered at 750 K. The changes in magnetic susceptibility, electric resistivity, thermopower and thermal conductivity associated with transitions in YCoO{sub 3} are discussed in comparison with similar data on related perovskite LaCoO{sub 3}.

• OSTI ID: 20788209
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 21 Vol. 73; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COBALT IONS
COBALT OXIDES
COMPARATIVE EVALUATIONS
CRYSTALS
ELECTRIC CONDUCTIVITY
GROUND STATES
MAGNETIC SUSCEPTIBILITY
NEUTRON DIFFRACTION
ORTHORHOMBIC LATTICES
PEROVSKITE
SPIN
SYMMETRY
TEMPERATURE DEPENDENCE
THERMAL CONDUCTIVITY
YTTRIUM COMPOUNDS