Phase equilibria and crystal chemistry of the R-Cu-Ti-O systems (R=lanthanides and Y)

Journal Article · Fri May 15 04:00:00 EDT 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2008.11.010· OSTI ID:21370390

Yang, Z ^[1]; Wong-Ng, W ^[2]; Kaduk, J A ^[3]; Jang, M ^[4]; Liu, G ^[2]

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1. Yunnan Normal University, Kunming 650092 (China)
2. Ceramics Division, National Institute of Standards and Technology, Giathersburg, MD 20899 (United States)
3. INEOS Technologies, Naperville, IL 60563 (United States)
4. Yonsei University, Seoul 120-740 (Korea, Republic of)

As part of the study of interaction of the Ba{sub 2}RCu{sub 3}O{sub 6+z} (R=lanthanides and Y) superconductor with SrTiO{sub 3} buffer, phase equilibria of the subsystem, R{sub 2}O{sub 3}-TiO{sub 2}-CuO (R=Nd, Y, and Yb), have been investigated in air at 960 deg. C. While the phase relationships of the two phase diagrams with smaller R (Y and Yb) are similar, substantial differences were found in the Nd{sub 2}O{sub 3}-TiO{sub 2}-CuO system, partly due to different phase formation in the binary R{sub 2}O{sub 3}-TiO{sub 2} and R{sub 2}O{sub 3}-CuO systems. R{sub 2}CuTiO{sub 6} and R{sub 2}Cu{sub 9}Ti{sub 12}O{sub 36} were the only ternary phases established in all the three diagrams. R{sub 2}Cu{sub 9}Ti{sub 12}O{sub 36} belongs to the perovskite-related [AC{sub 3}](B{sub 4})O{sub 12} family which is cubic Im3. Depending on the size of R{sup 3+}, R{sub 2}CuTiO{sub 6} crystallizes in two crystal systems: Pnma (R=La-Gd), and P6{sub 3}cm (R=Dy-Lu). The structure and crystal chemistry of the Pnma series of R{sub 2}CuTiO{sub 6} (R=La, Nd, Sm, Eu, and Gd) are discussed in detail in this paper. Patterns for selected members of R{sub 2}CuTiO{sub 6} have also been prepared and submitted for inclusion in the Powder Diffraction File (PDF). - Graphical abstract: Phase diagram of the Y{sub 2}O{sub 3}-CuO-TiO{sub 2} system prepared in air at 960 deg. C

• OSTI ID: 21370390
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 5 Vol. 182; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALKALINE EARTH METAL COMPOUNDS
CHALCOGENIDES
COHERENT SCATTERING
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTALS
CUBIC LATTICES
DIAGRAMS
DIFFRACTION
HEXAGONAL LATTICES
INFORMATION
MINERALS
ORTHORHOMBIC LATTICES
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PEROVSKITE
PEROVSKITES
PHASE DIAGRAMS
POWDERS
RARE EARTH COMPOUNDS
SCATTERING
STRONTIUM COMPOUNDS
STRONTIUM TITANATES
SUPERCONDUCTORS
TITANATES
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
X-RAY DIFFRACTION
YTTRIUM COMPOUNDS
YTTRIUM OXIDES