Abstract
The superconducting properties of the new high- T c compound YBa 2Cu 3O itx depend to a great extent on the stoichiometry parameter x, which in its turn depends on temperature and atmospheric conditions during preparation of the compound. To understand the relation between T c and x, it is necessary to have a detailed knowledge of the defect chemistry and the valencies of the constituent ions in YBa 2Cu 3O x . This knowledge can be obtained only if accurate data are available on the dependence of x on temperature and atmosphere. The present paper reports on a precision thermogravimetric determination of x for YBa 2Cu 3O x equilibrated at 400–900°C in almost pure oxygen. The results point to an asymptotic approach to x = 7 at low temperatures and a bending point in the x– T curve at x = 6.7. The data can be used as a basis for further defect chemistry studies. A preliminary interpretation indicates the presence of monovalent copper ions for the full stoichiometry range of x = 6–7.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
