Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-19T11:52:23.506Z Has data issue: false hasContentIssue false
  • English
  • Français

Pyrochlore to Fluorite Transitions – Ordering in Fluorites?

Published online by Cambridge University Press:  20 February 2017

Karl R. Whittle ,
Lachlan M. Cranswick ,
Simon A.T. Redfern ,
Ian P. Swainson  and
Gregory R. Lumpkin
Karl R. Whittle
Affiliation:
Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, PMB1, Menai, NSW 2234, Australia Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ, United Kingdom
Lachlan M. Cranswick
Affiliation:
Canadian Neutron Beam Centre, Chalk River National Laboratories, Ontario, Canada
Simon A.T. Redfern
Affiliation:
Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ, United Kingdom
Ian P. Swainson
Affiliation:
Canadian Neutron Beam Centre, Chalk River National Laboratories, Ontario, Canada
Gregory R. Lumpkin
Affiliation:
Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, PMB1, Menai, NSW 2234, Australia
Get access

Abstract

Two systems have been studied La2-xYxZr2O7 and La2-xYxHf2O7, as part of an on-going study of radiation tolerance in nuclear waste forms and related oxide materials. The structural effects of increasing Y content in La based zirconate and hafnate pyrochlores have been studied with neutron diffraction and electron microscopy. Results have shown a difference in structural stability for both the pyrochlore and fluorite phases within each system, including the presence of two-phase regions in both systems. In the zirconate, the two-phase region lies in the range x = 0.9-1.6. This is shifted to higher Y content in the hafnate system and lies in the range of x = 1.5 to approximately 1.8-1.9. In addition to the differences in phase stability, electron diffraction, predominantly down the [110] zone axis, has shown evidence for ordering in the form of structured diffuse scattering within the fluorite phases.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1122: Symposium O – Structure/Property Relationships in Fluorite-Derivative Compounds , 2008 , 1122-O03-01
Copyright
Copyright © Materials Research Society 2009

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. Kim, N.; Grey, C. P., Journal of Solid State Chemistry 2003, 175, (1), 110–115.Google Scholar
2. Lian, J.; Wang, L. M.; Wang, S. X.; Chen, J.; Boatner, L. A.; Ewing, R. C., Physical Review Letters 2001, 8714, (14), art. no.-145901.Google Scholar
3. Poulsen, F. W.; Glerup, M.; Holtappels, P., Solid State Ionics 2000, 135, (1–4), 595–602.Google Scholar
4. Wilde, P. J.; Catlow, C. R. A., Solid State Ionics 1998, 112, (3–4), 185–195.Google Scholar
5. Wang, S. X.; Begg, B. D.; Wang, L. M.; Ewing, R. C.; Weber, W. J.; Kutty, K. V. G., Journal of Materials Research 1999, 14, (12), 4470–4473.Google Scholar
6. Wang, S. X.; Wang, L. M.; Ewing, R. C.; Kutty, K. V. G., Nuclear Instruments & Methods in Physics Research Section B- Beam Interactions with Materials and Atoms 2000, 169, 135–140.Google Scholar
7. Yudintsev, S. V., Geology of Ore Deposits 2003, 45, (2), 151–165.Google Scholar
8. Chakoumakos, B. C., Journal of Solid State Chemistry 1984, 53, (1), 120–129.Google Scholar
9. Subramanian, M. A.; Aravamudan, G.; Rao, G. V. S., Progress in Solid State Chemistry 1983, 15, (2), 55–143.Google Scholar
10. Lian, J.; Chen, J.; Wang, L. M.; Ewing, R. C.; Farmer, J. M.; Boatner, L. A.; Helean, K. B., Physical Review B 2003, 68, (13), art. no.-134107.Google Scholar
11. Meldrum, A.; Boatner, L. A.; Ewing, R. C., Physical Review Letters 2002, 8802, (2), art. no.-025503.Google Scholar
12. Zhu, S.; Zu, X. T.; Wang, L. M.; Ewing, R. C., Applied Physics Letters 2002, 80, (23), 4327–4329.Google Scholar
13. Lian, J.; Zu, X. T.; Kutty, K. V. G.; Chen, J.; Wang, L. M.; Ewing, R. C., Physical Review B 2002, 66, (5), 054108.Google Scholar
14. Rietveld, H. M., Journal of Applied Crystallography 1969, 2, 65–71.Google Scholar
15. Larson, A. C.; Von Dreele, R. B. General Structure Analysis System (GSAS); 86–748; Los Alamos National Laboratory Report LAUR: 2000.Google Scholar
16. Toby, B. H., Journal of Applied Crystallography 2001, 34, 210–213.Google Scholar
17. Tabira, Y.; Withers, R. L.; Yamada, T.; Ishizawa, N., Zeitschrift Fur Kristallographie 2001, 216, (2), 92–98.Google Scholar
18. Harvey, E. J.; Whittle, K. R.; Lumpkin, G. R.; Smith, R. I.; Redfern, S. A. T., Journal Of Solid State Chemistry 2005, 178, (3), 800–810.Google Scholar