Hostname: page-component-78c5997874-t5tsf Total loading time: 0 Render date: 2024-11-19T09:21:01.747Z Has data issue: false hasContentIssue false

Neutron Rietveld Analysis of Anion and Cation Disorder in the Fast-Ion Conducting Pyrochlore System Y2(ZrxTi1−x)2O7

Published online by Cambridge University Press:  21 February 2011

Sossina M. Haile
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
B. J. Wuensch
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
E. Prince
Affiliation:
Reactor Radiation Division, National Institute of Standards and Technology, Gaithersburg, MD 20899
Get access

Abstract

All information on the site occupancies and atomic displacements which relate a pyrochlore superstructure to the parent fluorite-type subcell is contained in the normally-weak superstructure diffraction intensities. As Ti has a negative scattering length, the supercell maxima in the present phases are up to three times as intense as the fluorite-like reflections, and neutron diffraction provides an especially sensitive probe of the state of disorder. Y2Ti2O7 is found to have a fullyordered anion array and slight disorder, Y0.984Ti0.015, among the cations. In Y2(Zro.6TiO.4)2O7 the oxygen site normally vacant in pyrochlore is half filled and on the order of 15% exchange between cation sites has occurred.

Type
Research Article
Copyright
Copyright © Materials Research Society 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Dijk, T. van, Helmholdt, R. B. and Burggraaf, A. J., Phys. Stat. Sol. (b) 101, 765 (1980).Google Scholar
2. Dijk, M. P. van, Burggraaf, A. J., Cormack, A. N., and Catlow, C. R. A., Solid State Ionics 17, 159 (1985).Google Scholar
3. Moriga, T., Yoshiasa, A., Kanamaru, F., Koto, K., Yoshimura, M. and Somiya, S., Solid State Ionics 31 319 (1989).Google Scholar
4. Moon, P. K. and Tuller, H. L., Solid State Ionics 28–30 470 (1988); Mater. Res. Soc. Proc. 135, Pittsburgh, PA 1989, pp. 149-163.Google Scholar
5. Rietveld, H. M., J. Appl. Cryst. 2, 65 (1969).Google Scholar