Valence states and local environment of thallium and copper ions in some new high T sub c superconductors by XAS--

Journal Article · Sat Jul 01 04:00:00 EDT 1989 · International Journal of Modern Physics B; (USA)

DOI:https://doi.org/10.1142/S0217979289000749· OSTI ID:7171812

Studer, F; Retoux, R; Martin, C; Michel, C; Raveau, B ^[1]; Dartyge, E; Fontaine, A; Tourillon, G ^[2]

---

1. Laboratoire de Cristallographie et Sciences des Materiaux, ISMRa, Bd du Marechal Juin, Universite de Caen, 14032 Caen Cedex, (FR)
2. LURE, CNRS-MEN-CEA, 91405 Orsay Cedex (FR)

This paper reports the valence states of cations inside for high T{sub c} thallium superconductors investigated by X-ray absorption spectroscopy at thallium L{sub III}, L{sub I} and copper K-edges. The thallium ions are observed on L{sub III} and L{sub I} edges in the Tl(III) valence state (empty 6s levels) in spite of large Tl-O distances in the (a,b) plane of the structure as deduced from X-ray diffraction. The presence of two types of Tl-O distances have been well established on XANES spectra and the F.T of EXAFS have shown the presence of two very short Tl-O bonds (2.03 A). The copper K-edges are characterized by the absence of Cu(I) state (3d{sup 10} line).

• OSTI ID: 7171812
• Journal Information: International Journal of Modern Physics B; (USA), Journal Name: International Journal of Modern Physics B; (USA) Vol. 3:7; ISSN 0217-9792; ISSN IJPBE
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202 -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400101 -- Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CATIONS
CHARGED PARTICLES
CHEMICAL BONDS
COPPER
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DISLOCATIONS
EDGE DISLOCATIONS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
IONIC CONDUCTIVITY
IONS
LINE DEFECTS
METALS
PHYSICAL PROPERTIES
SPECTRA
SUPERCONDUCTIVITY
SUPERCONDUCTORS
THALLIUM COMPOUNDS
THALLIUM IONS
TRANSITION ELEMENTS
VALENCE
X-RAY SPECTRA