Does local disorder occur in the pyrochlore zirconates?
The zirconates Ln(2)Zr(2)O(7) (Ln = lanthanoid) have been studied using a combination of Zr L-edge X-ray absorption near edge structure (XANES) and synchrotron X-ray and neutron powder diffraction methods. These studies demonstrate that as the size of the lanthanoid cation decreases, the local structure evolves smoothly from the ideal pyrochlore toward the defect fluorite rather than undergoing an abrupt transformation. The Zr L-edge spectrum is found to be extremely sensitive to changes in the local coordination environment and demonstrates an increase in local disorder across the pyrochlore oxides. The sensitivity of the XANES measurements enables us to identify the progressive nature of the transition that could not be detected using bulk diffraction techniques.
School of Chemistry, The University of Sydney, Sydney, NSW 2006 Australia.
Peter E R
PE
Blanchard
Richard
R
Clements
Brendan J
BJ
Kennedy
Chris D
CD
Ling
Emily
E
Reynolds
Max
M
Avdeev
Anton P J
AP
Stampfl
Zhaoming
Z
Zhang
Ling-Yun
LY
Jang