Synthesis and crystal chemistry of the new compounds GdBa{sub 4}Cu{sub 3}O{sub 8.5+{delta}} and DyBa{sub 4}Cu{sub 3}O{sub 8.5+{delta}}
- Mail Stop K763, Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Two new compounds, GdBa{sub 4}Cu{sub 3}O{sub 8.5+{delta}} (Gd143) and DyBa{sub 4}Cu{sub 3}O{sub 8.5+{delta}} (Dy143), were synthesized from precursors Gd{sub 2}O{sub 3}, Dy{sub 2}O{sub 3}, BaO{sub 2}, and CuO at 1000&hthinsp;{degree}C in an oxygen atmosphere. The oxygen stoichiometric value {delta} was found to be 0.68 for Gd143 and 0.6 for Dy143 by iodometric titration. Rietveld refinement of x-ray powder diffraction data showed that Gd143 belongs to the space group {ital Pm}3 while Dy143 belongs to the space group {ital P}23. The two space groups, {ital Pm}3 and {ital P}23, are very similar. Their main difference is that {ital P}23 does not have the inversion symmetry of {ital Pm}3. Both compounds have a cubic unit cell with a lattice parameter of 8.16528thinsp{plus_minus}thinsp0.00006thinsp{Angstrom} for Gd143 and 8.10807thinsp{plus_minus}thinsp0.00010thinsp{Angstrom} for Dy143. Superconducting quantum interference device (SQUID) measurement indicated that neither compound was superconductive down to 5 K. {copyright} {ital 1999 Materials Research Society.}
- Research Organization:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 341166
- Journal Information:
- Journal of Materials Research, Vol. 14, Issue 2; Other Information: PBD: Feb 1999
- Country of Publication:
- United States
- Language:
- English
Similar Records
Powder diffraction data of SmBa{sub 4}Cu{sub 3}O{sub 8.5+{delta}}
Positron annihilation in the epitaxial superconducting thin-film GdBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} studied by using a pulsed positron beam