ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Oxygen Content Effect in Y—Ba—Сu—О Superconductors

M. Breza

Department of Chemical Physics, Faculty of Chemical Technology, Slovak Technical University

Abstract: The dependence of electronic structure of superconducting YBa₂Cu₃Oy on the oxygen content is investigated using the standard CNDO/2 and quasi-relativistic CNDO/1 molecular orbital method. Electronic structures of model clusters [Cu₃O_n]^q with total charges q = 7 - 2n and n = 11 to 14 in various geometries are compared. Possible Cu(III) in real systems may be ascribed to penta-coordinate Cu-2 in CuO₂ planes for y < 7 or to Cu-1 in Cu-O chains for y > 7. The apical oxygen position within Cu-1-O-2-Cu-2 frame is influenced by actual Cu-1 coordination implied by the y value.

Full paper in Portable Document Format: 473a137.pdf

Chemical Papers 47 (3) 137–142 (1993)