Chemistry and structural modulations in Bi sub 2 Sr sub 2 CuO sub 6

Journal Article · Wed Apr 01 04:00:00 EST 1992 · Journal of Materials Research; (United States)

DOI:https://doi.org/10.1557/JMR.1992.0844· OSTI ID:7048375

Shen, Y; Richards, D R; Hinks, D G; Mitchell, A W ^[1]

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1. Materials Science Division and Science and Technology Center for Superconductivity, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

A series of samples along the composition lines Bi{sub 2+{ital x}}Sr{sub 2{minus}{ital x}}CuO{sub {ital y}} and Bi{sub 2}Sr{sub 2{minus}{ital x}}CuO{sub {ital y}} have been used to study the structural modulation, chemistry, and superconducting properties of pseudo-tetragonal Bi{sub 2}Sr{sub 2}CuO{sub 6}(2201). The 2201 phase can be formed from crystallization of thin glassy platelets. The sample displayed a strong crystallographic (00{ital l}) orientation which made it possible to determine incommensurate modulations near (00{ital l}) reflections using a conventional x-ray {theta}-2{theta} scan. From the crystallization of the 2201 phase, it was found that structural modulation was intrinsic to the phase, and ordering of the structure required a long time at high temperature. High temperature {ital in} {ital situ} x-ray diffraction of a 2201 Bi{sub 2}Sr{sub 1.85}CuO{sub {ital y}} platelet showed that the modulation existed at 875 {degree}C in O{sub 2} ({ital T}{sub melt} {approx}892 {degree}C in O{sub 2}). These suggest that the structural modulation cannot be caused solely by oxygen ordering and that metal-ion displacement must be involved. By removing 0.04 to 0.05 oxygen atom per formula unit from Bi{sub 2}Sr{sub 2}CuO{sub {ital y}} and Bi{sub 2}Sr{sub 1.85}CuO{sub {ital y}}, the {bold c}* components of the modulation changed from 0.31 to 0.26 and from 0.38 to 0.31, respectively, while the {bold b}* component of the modulation remained approximately 0.2. This demonstrates that oxygen, while not the sole cause, does play a role in the formation of the structural modulation. However, the invariance of {ital b}{sub mod} with respect to the change in oxygen content does not support the model that explained the modulation by inserting extra oxygen in the BiO plane.

• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 7048375
• Journal Information: Journal of Materials Research; (United States), Journal Name: Journal of Materials Research; (United States) Vol. 7:4; ISSN JMREE; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360207 -- Ceramics
Cermets
& Refractories-- Superconducting Properties-- (1992-)
ALKALINE EARTH METAL COMPOUNDS
ALKALINE EARTH METALS
BISMUTH
BISMUTH COMPOUNDS
BISMUTH OXIDES
CHALCOGENIDES
CHEMICAL COMPOSITION
CHEMISTRY
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL STRUCTURE
CRYSTALLOGRAPHY
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
HIGH-TC SUPERCONDUCTORS
METALS
NONMETALS
OXIDES
OXYGEN
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
QUANTITY RATIO
STRONTIUM
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SUPERCONDUCTIVITY
SUPERCONDUCTORS
TEMPERATURE RANGE
TEMPERATURE RANGE 1000-4000 K
TRANSITION ELEMENT COMPOUNDS