Preparation and Chemical Composition of Superconducting Oxide Tl2Ba2Can-1CunO2n+4 with n{=}1, 2 and 3
Abstract
Superconducting oxides of Tl2Ba2Can-1CunO2n+4 with n{=}1, 2 and 3 were synthesized, and their structure and chemical composition were examined by X-ray powder diffraction, EPMA, Rietveld analysis and electron microscopy. Partial substitution of Tl with Ca was confirmed, but the production of holes in Cu layers expected from this substitution was rather small for a 120 K superconductor. Charge transfer of Tl3-δ-Cu2+δ would provide both the hole in the Cu-O bond required for high Tc and s-like electron of Tl atoms for stabilization of layered structures.
- Publication:
-
Japanese Journal of Applied Physics
- Pub Date:
- March 1989
- DOI:
- 10.1143/JJAP.28.L382
- Bibcode:
- 1989JaJAP..28L.382K
- Keywords:
-
- Chemical Composition;
- Crystal Structure;
- High Temperature Superconductors;
- Mixed Oxides;
- Thallium Compounds;
- Barium Oxides;
- Calcium Oxides;
- Copper Oxides;
- Electron Microscopy;
- X Ray Diffraction;
- Solid-State Physics