Phase relation and heat capacities of Ba sub 2 YCu sub 3 O sub 7 minus x at high temperature

Journal Article · Mon Oct 01 04:00:00 EDT 1990 · Journal of Solid State Chemistry; (USA)

DOI:https://doi.org/10.1016/0022-4596(90)90257-X· OSTI ID:6083623

Matsui, Tsuneo; Fujita, Tooru; Naito, Keiji ^[1]; Takeshita, Takuo ^[2]

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1. Nagoya Univ. (Japan)
2. Mitsubishi Metal Corp., Saitama (Japan)

The heat capacities of Ba{sub 2} YCu{sub 3}O{sub 7{minus}x} (x = 0.18, 0.35, and 0.60) were measured in the range from room temperature to 860 K by an adiabatic scanning calorimeter. X-ray diffraction analyses were also performed on the quenched and annealed samples. No heat capacity anomaly was seen in either orthorhombic(I) Ba{sub 2}YCu{sub 3}O{sub 6.82} or tetragonal Ba{sub 2}YCu{sub 3}O{sub 6.40}. For Ba{sub 2}YCu{sub 3}O{sub 6.65}, the heat capacity anomaly was observed above 700 K, which was correlated with the phase transition from orthorhombic(I) to orthorhombic(II) structure. The phase relations among orthorhombic(I), orthorhombic(II), and the tetragonal phases were also clarified.

• OSTI ID: 6083623
• Journal Information: Journal of Solid State Chemistry; (USA), Journal Name: Journal of Solid State Chemistry; (USA) Vol. 88:2; ISSN JSSCB; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure & Phase Studies
360603 -- Materials-- Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METALS
BARIUM
CALORIMETRY
COHERENT SCATTERING
COPPER COMPOUNDS
CUPRATES
DATA
DIFFRACTION
ELEMENTS
EXPERIMENTAL DATA
HIGH TEMPERATURE
HIGH-TC SUPERCONDUCTORS
INFORMATION
METALS
NUMERICAL DATA
OXYGEN COMPOUNDS
PHASE STUDIES
PHYSICAL PROPERTIES
SCATTERING
SPECIFIC HEAT
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
X-RAY DIFFRACTION
YTTRIUM