Short-range ordering due to displacements of thallium and oxygen atoms in superconducting Tl/sub 2/Ba/sub 2/CaCu/sub 2/O/sub 8/ observed by pulsed-neutron scattering

Journal Article · Mon Nov 28 00:00:00 EST 1988 · Phys. Rev. Lett.; (United States)

OSTI ID:6729551

Dmowski, W; Toby, B H; Egami, T; Subramanian, M A; Gopalakrishnan, J; Sleight, A W

The atomic positional correlations in superconducting Tl/sub 2/Ba/sub 2/CaCu/sub 2/O/sub 8/ were studied by pair distribution function analysis of the pulsed-neutron scattering data. The results show for the first time strongly correlated local displacements of both thallium and oxygen atoms in the Tl-O plane from the high-symmetry crystallographic sites. As a consequence of the displacements Tl atoms form chains or pairs accompanied by displacement of nearby oxygen atoms, resulting in locally orthorhombic order. The ordering, however, remains very much short range and does not alter the average symmetry. The implications of these results with regard to the superconductivity of these oxides are discussed.

• Research Organization: Department of Materials Science and Engineering, and Laboratory for Research on the Structure of Matter, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6272
• OSTI ID: 6729551
• Journal Information: Phys. Rev. Lett.; (United States), Vol. 61:22
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM COMPOUNDS
INTERACTION RANGE
ORDER PARAMETERS
CALCIUM COMPOUNDS
COPPER OXIDES
OXYGEN
MOTION
THALLIUM
THALLIUM COMPOUNDS
CHAINS
DISTRIBUTION FUNCTIONS
NEUTRON DIFFRACTION
PULSES
SUPERCONDUCTORS
ALKALINE EARTH METAL COMPOUNDS
CHALCOGENIDES
COHERENT SCATTERING
COPPER COMPOUNDS
DIFFRACTION
DISTANCE
ELEMENTS
FUNCTIONS
METALS
NONMETALS
OXIDES
OXYGEN COMPOUNDS
SCATTERING
TRANSITION ELEMENT COMPOUNDS
360202* - Ceramics
Cermets
& Refractories- Structure & Phase Studies