Oxygen stoichiometry and structural parameters of Sm1+xBa2−xCu3Oy solid solutions versus composition and temperature

• Published in: Journal of alloys and compounds Vol. 384; no. 1-2; pp. 44 - 50
• Main Authors: Drozd, V.A., Baginski, I.L., Nedilko, S.A., Mel’nikov, V.S.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 14.12.2004; Elsevier
• Subjects: Electronic transport; Exact sciences and technology; High-Tc superconductors; Physics; Sol–gel synthesis; X-ray diffraction; X-ray diffraction; Sol–gel synthesis; Electronic transport; High-Tc superconductors; Solid solutions; Temperature effects; Rare earths; Orthorhombic lattices; Samarium; Lattice parameters; Sol-gel process; Nonstoichiometry; Sol-gel synthesis
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2004.03.125

The effects of temperature and samarium content on oxygen stoichiometry and crystal lattice parameters of the Sm1+xBa2−xCu3Oy solid solutions (Sm123ss) prepared by the citrate sol–gel method were studied. It was found that there are three compositional ranges of variation of the structural-chemical characteristics of the Sm123ss corresponding to the regions of existence of the following three phases: orthorhombic phase I (0≤x<0.15–0.20), tetragonal phase (0.20≤x<0.60) and orthorhombic phase II (x≥0.65). The above phases behave differently with temperature: (a) the orthorhombic phase I behaves with temperature like the Y123 phase; (b) the lattice parameters a and c of the tetragonal phase vary, i.e., its lattice is relatively rigid as oxygen is removed; (c) the orthorhombic phase II has a very rigid crystal lattice.