ISSN:
1572-9605
Keywords:
layered compounds
;
8-8-20
;
x-ray diffraction
;
electrical properties
Source:
Springer Online Journal Archives 1860-2000
Topics:
Electrical Engineering, Measurement and Control Technology
,
Physics
Notes:
Abstract With an attempt to increase the Cu valence, we synthesized the (La1−x Sr x )8Cu8O20−δ (8-8-20 phase) compounds with large x using an O2-HIP apparatus. By heat treatment in a high-pressure of oxygen gas (40 MPa), the 8-8-20 compounds were stabilized in the range of 0.25 ≤ x ≤ 0.65. Their crystal structures, characterized by x-ray Rietveld refinement and electron diffraction, are tetragonal, space group P4/mbm. The formal copper valence was found to increase with Sr concentration from 2.24 at x = 0.25 to 2.63 at x = 0.65, keeping the oxygen content constant around 20.0. Electrical resistivity and magnetic susceptibility showed only metallic behavior from room temperature down to 5 K with no sign of superconductivity.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007731915362
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