Synthesis and structure of a new perovskite, SrCuO{sub 2.5}
- Columbia Univ., Palisades, NY (United States)
- IBM Thomas J. Watson Center, Yorktown Heights, NY (United States); and others
A new oxygen-deficient perovskite, SrCuO{sub 2.5}, was prepared at 950{degrees}C and 100 kbar pressure in a multianvil apparatus. Rietveld profile analysis, using X-ray powder diffraction data, was employed for the structural determination. SrCuO{sub 2.5} is orthorhombic, Pbam (No. 55), Z = 4, a = 5.424(2) {angstrom}, b = 10.837(4) {angstrom}, and c = 3.731(1) {angstrom}, which is related to the perovskite subcell by {radical}2a{sub p} x 2{radical}2ap x a{sub p}, where a{sub p} is the simple cubic perovskite lattice parameter. It consists of corner-shared CuO{sub 5} square pyramids with oxygen vacancy ordering in the CuO{sub 2} layers. The ordered oxygen vacancies create parallel pseudo-hexagonal tunnels where the Sr atoms reside, forming SrO{sub 10} polyhedra. Structural features with respect to oxygen vacancies, superstructures, and distortions are analogous to the type of ordering observed in Sr{sub 2}CuO{sub 3+{delta}}. Superconductivity was not observed in SrCuO{sub 2.5} down to 5 K.
- OSTI ID:
- 223747
- Journal Information:
- Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 2 Vol. 121; ISSN 0022-4596; ISSN JSSCBI
- Country of Publication:
- United States
- Language:
- English
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