Magnetic and charge transport properties of the Na-based Os oxide pyrochlore

Journal Article · Wed Apr 15 00:00:00 EDT 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.01.008· OSTI ID:21370352

Belik, A A ^[1]; Tachibana, M; Tanaka, M ^[2]; Katsuya, Y ^[3]; Kobayashi, K ^[2]; Yamaura, K ^[4]; Takayama-Muromachi, E ^[4]

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1. International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan)
2. NIMS Beamline Station at SPring-8, National Institute for Materials Science, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan)
3. JST, Transformative Research-Project on Iron Pnictides (TRIP), Tsukuba, Ibaraki 305-0044 (Japan)
4. Superconducting Materials Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

The Na-based osmium oxide pyrochlore was synthesized for the first time by an ion-exchange method using KOs{sub 2}O{sub 6} as a host. The composition was identified as Na{sub 1.4}Os{sub 2}O{sub 6}.H{sub 2}O by electron probe micro-analysis, thermogravimetric analysis, and structural analysis using synchrotron X-ray diffraction. Na{sub 1.4}Os{sub 2}O{sub 6}.H{sub 2}O crystallizes in a regular pyrochlore structure with some defects (space group: Fd-3m, a=10.16851(1) A). Electrical resistivity, heat capacity, and magnetization measurements clearly showed absence of superconductivity down to 2 K, being in large contrast to what was found for the beta-type pyrochlore superconductor AOs{sub 2}O{sub 6} (A=Cs, Rb, and K). The Sommerfeld coefficient is 22 mJ K{sup -2} mol{sup -1}, being the smallest among AOs{sub 2}O{sub 6}. A magnetic anomaly at {approx}57 K and associated magneto-resistance (+3.7% at 2 K in 70 kOe) were found. - Graphical abstract: Crystal structure of the Na-based Os oxide pyrochlore Na{sub 1.4}Os{sub 2}O{sub 6}.H{sub 2}O.

• OSTI ID: 21370352
• Journal Information: Journal of Solid State Chemistry, Vol. 182, Issue 4; Other Information: DOI: 10.1016/j.jssc.2009.01.008; PII: S0022-4596(09)00012-7; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CHARGE TRANSPORT
CRYSTAL STRUCTURE
ELECTRON MICROPROBE ANALYSIS
ION EXCHANGE
MAGNETIC PROPERTIES
MAGNETIZATION
MAGNETORESISTANCE
OSMIUM OXIDES
POTASSIUM COMPOUNDS
PYROCHLORE
SODIUM COMPOUNDS
SPACE GROUPS
SPECIFIC HEAT
SUPERCONDUCTIVITY
SUPERCONDUCTORS
THERMAL GRAVIMETRIC ANALYSIS
WATER
X-RAY DIFFRACTION
ALKALI METAL COMPOUNDS
CHALCOGENIDES
CHEMICAL ANALYSIS
COHERENT SCATTERING
DIFFRACTION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
GRAVIMETRIC ANALYSIS
HYDROGEN COMPOUNDS
MICROANALYSIS
MINERALS
NONDESTRUCTIVE ANALYSIS
OSMIUM COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
QUANTITATIVE CHEMICAL ANALYSIS
REFRACTORY METAL COMPOUNDS
SCATTERING
SYMMETRY GROUPS
THERMAL ANALYSIS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS