Theoretical studies of copper oxide clusters: Prediction of an electronically driven phase separation in YBa/sub 2/Cu/sub 3/O/sub x/

Conference · Sun Nov 01 04:00:00 EST 1987

OSTI ID:5484736

Curtiss, L A; Brun, T O; Gruen, D M

On the basis of semi-empirical extended Hueckel molecular orbital calculations of copper-oxide clusters representing the new superconducting material YBa/sub 2/Cu/sub 3/O/sub x/, a phase diagram is proposed which suggests that the 94/sup 0/K high-temperature superconducting phase of YBa/sub 2/Cu/sub 3/O/sub x/ is characterized by an oxygen stoichiometry near 7.0. The phase diagram predicts that a plateau should exist for T/sub c/ in the region x = 0.0 to 0.25 and that in this region two phases are present which are characterized by compositions having oxygen stoichiometries 6.5 to 6.75 and ca. 7.0. 15 refs., 2 figs., 1 tab.

• Research Organization: Argonne National Lab., IL (USA)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5484736
• Report Number(s): CONF-871124-82; ON: DE88005977
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
DIAGRAMS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
MOLECULAR ORBITAL METHOD
NONMETALS
OXIDES
OXYGEN
OXYGEN COMPOUNDS
PHASE DIAGRAMS
PHYSICAL PROPERTIES
STOICHIOMETRY
SUPERCONDUCTIVITY
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
VALENCE
YTTRIUM COMPOUNDS
YTTRIUM OXIDES