Crystal structure and superconductivity of the Mo-stabilized Sr-based YSr{sub 2}Cu{sub 2.7}Mo{sub 0.3}O{sub 7-{delta}} compound

Journal Article · Thu Sep 01 04:00:00 EDT 1994 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1006/jssc.1994.1289· OSTI ID:518212

Hu, S F; Jefferson, D A ^[1]; Liu, R S; Shy, D S ^[2]; Su, S C ^[3]

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1. Univ. of Cambridge (United Kingdom)
2. Industrial Technology Research Inst., Hsinchu (Taiwan, Province of China)
3. Pacific Electric Wire and Cable Co., Ltd., Tao-Yuan (Taiwan, Province of China)

The crystal structure of the Mo-stabilized Sr-based superconductor with nominal composition YSr{sub 2}Cu{sub 2.7}Mo{sub 0.3}O{sub 7-{delta}} has been analyzed by X-ray powder diffraction (XRD), electron diffraction, and high-resolution electron microscope techniques. The material crystallizes in the space group P4/mmm, with lattice parameters a = 3.8138(2) and c = 11.5204(8) {angstrom}. In the structure, the Mo ions are exclusively substituted for copper and are located mainly on the planar coordinated [Cu(2)] sites ({approximately}24%), with only a small proportion on the chain [Cu(1)] sites ({approximately} 6%) in the parent YBa{sub 2}Cu{sub 3}O{sub 7}(123-type) structure. A disordering of the hole reservoir layer [Mo(1)/Cu(1)]-O(3) due to the displacement of the oxygen ions [O(3)] from their ideal positions of (0,0.5,0) to (0.13,0.5,0) was found in the XRD refinement, but neither a superlattice nor any form of intergrowth along the a* and c* directions was observed by electron diffraction and high-resolution electron microscopy. The chemical substitution of copper by molybdenum renders the YSr{sub 2}Cu{sub 3}O{sub 7} compound superconducting, with T{sub c} up to 45 K.

• OSTI ID: 518212
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 1 Vol. 112; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COPPER OXIDES
CRYSTAL STRUCTURE
ELECTRON DIFFRACTION
LATTICE PARAMETERS
MOLYBDENUM OXIDES
STRONTIUM OXIDES
SUPERCONDUCTIVITY
YTTRIUM OXIDES