In:
Modern Physics Letters B, World Scientific Pub Co Pte Ltd, Vol. 04, No. 08 ( 1990-04-20), p. 535-543
Abstract:
Near neighboring structures around Fe in YBa 2 ( Cu 1−x Fe x ) 3 O 7−y with nominal values of x = 0.07 and 0.10, were determined using extended X-ray absorption fine structure measurements. The results show that substitutional Fe cations are located at Cu(1) site, and essential structures around Fe are similar to those around Cu(1) in YBa 2 Cu 3 O 7−y , but bond lengths of Fe–O(4) and Fe–O(1) are shrunk as compared with those of Cu(1)–O(4) and Cu(1)–O(1) in YBa 2 Cu 3 O 7−y due to the substitution of Cu by Fe. The interesting result is that extra oxygen anions are introduced located at O(5) sites near the substitutional Fe cation and the number of these oxygen anions apparently increases with the content of Fe in the compounds. It can be estimated that substitutional Fe in Y–Ba–Cu–O system has more than one coordination geometries, but has distorted octahedral coordination in a statistical sense. In combination with the superconductivity in these compounds, it is suggested that Cu–O structure on the basal plane of unit cell in YBa 2 Cu 3 O 7−y plays an important role in high-T c superconductivity.
Type of Medium:
Online Resource
ISSN:
0217-9849
,
1793-6640
DOI:
10.1142/S0217984990000684
Language:
English
Publisher:
World Scientific Pub Co Pte Ltd
Publication Date:
1990
