[Y1-xCax]SrBaCu2.80 (PO4)0.20Oy samples with 0.10≤x≤0.40 were synthesized using the solid state reaction technique. X-ray diffraction patterns show that all the compounds crystallized into a 123 tetragonal structure. The analyses of the structure with Rietveld refinement were made using a model that contain one Cu(2) in a four coordination and not in five coordination as the other 123 tetragonal structures. This fact permits that the Tc increases with Ca concentration. All samples are superconductors as reported previously.
Bibliographical noteFunding Information:
This work at the Universidad Nacional Mayor de San Marcos was supported by the Superior Council of Research (SRC) under contract # 91301031. J. Albino Aguiar, and D.A. Landinez Tellez thanks Brazilian Research Agencies CNPq, FACEPE and FINEP for financial support.
- [YCa]SrBaCu (PO)O
- Rietveld refinement