Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-27T01:56:31.003Z Has data issue: false hasContentIssue false
  • English
  • Français

Analysis of Coordination Polyhedra Symmetry in Pyrochlore and Zirconolite Structures

Published online by Cambridge University Press:  10 February 2011

A. Y. Troole  and
S. V. Stefanovsky
A. Y. Troole
Affiliation:
SIA "Radon", 7th Rostovskii per. 2/14, Moscow 119121 Russia, [email protected]
S. V. Stefanovsky
Affiliation:
SIA "Radon", 7th Rostovskii per. 2/14, Moscow 119121 Russia, [email protected]
Get access

Abstract

Zirconolite and pyrochlore are considered as promising host phases for high level waste (HLW). However, correct information on substitution mechanisms, forms of dopants incorporation in their structures and distortions in coordination polyhedra is presently unavailable. To clarify these points we use the electron paramagnetic resonance (EPR). Pyrochlore and three of zirconolite polytypes: zirconolite-2M, zirconolite-3T, and zirconolite-30 are considered. Pyrochlore is the “parent” structure for zirconolite since any zirconolite variety is produced by means of distortion of the initial pyrochlore structure. Space groups of pyrochlore and basic polymorphous zirconolite varieties found from XRD and TEM data, as well as interatomic distances and angles, were taken from reference data. This allows the determination of the most probable sites for impurities, substitution mechanisms, and local symmetry of coordination polyhedra (initial). Ions chosen for EPR were Gd (III) as an analog of trivalent rare earth and actinide elements which are also occurred in HLW and Fe (III) as a typical corrosion product which occurs in all HLW. For Gd (III) a strong ligand field approximation is suggested, theoretical computation using perturbation theory in this approximation has been carried out. All the non-diagonal members plus magnetic field were chosen as perturbation and formulae for transition frequencies, estimations of fine structure and g-factors parameters in the given approximation have been obtained.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 556: Symposium QQ – Scientific Basis for Nuclear Waste Management XXII , 1999 , 35
Copyright
Copyright © Materials Research Society 1999

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. Aleshin, E., Roy, R., J. Amer. Cream. Soc. 45, 18 (1962).Google Scholar
2. Chakoumakos, B. C., Ewing, R. C., in Sciefnlific Basis for Nuclcear Wascle Management IX edited by Jantzen, C. M., Stone, J. A. and Ewing, R. C. (Mat. Res. Soc. Symp. Proc 44, Pittsburgh, PA, 1985) pp. 641–646.Google Scholar
3. Lumpkin, G., Ewing, E. C., Phys. Chem.Minerals 16, 2 (1988).Google Scholar
4. Ewing, R. C., Weber, W. J., Lutze, W., Dissposal of Weapon Plutonium, edited by Merz, E. R. and Walter, C. E. (Kluwer Academic Publishers, Amsterdam, 1996) pp. 65–83.Google Scholar
5. Lumpkin, G. R., Ewing, R. C., Chakoumakos, B. C., Greegor, R. B, Lytle, F. W.; Foltyln, E. M, Clinard, F. W. Jr., Boatner, L. A., Abraham, M. M., J. Mater. Res. 1, 564 (1986).Google Scholar
6. Gatehouse, B.M., Grey, I.E., Roderick, J.H., Rossell, H.J., Acta Cryst. B 37, 306 (1981).Google Scholar
7. Mazzi, F., Munno, R., Amer. Mineral. 68, 262 (1983).Google Scholar
8. Vance, E. R., Begg, B. D., Day, R. A., Ball, C. J., in Scientific Basis for Nuclear’ Wast/Manatigemet XVIII, edited by Murakami, T. and Ewing, R. C. (Mat. Res. Sos. Symp. Proc. 353 Pittsburgh, PA, 1995), pp. 767–774.Google Scholar
9. Vance, E. R., Jostsons, A., Day, R. A., Ball, C. J., Begg, B. D., in Scientific Bcasis for Nuclear Waste Mancagement XV7III, edited by Murphy, W. M. and Knecht, D. A. (Mat. Res. Soc. Symp. Proc. 412, Pittsburgh, PA, 1996) pp, 41–47.Google Scholar
10. Vance, E. R., Hart, K. P., Day, R. A., Begg, B. D., Angell, P. J., Loi, E., Weir, J., Oversby, V. M., in scientific Basis for Nuclear Waste Mtnagemente Xl'lll, edited by Murphy, W. M. and D.A, Knecht (Mat. Res. Soc. Symp. Proc. 412, Pittsburgh, PA, 1996) pp. 49–55.Google Scholar
11. Rappaz, M., Abraham, M. M., Ramey, J. O., Boatner, L. A., Phys. Rev. B 23, 1012 (1981).Google Scholar
12. Troole, A. Y., Stefanovsky, S. V., Bogomolova, L. D.. Phys. Chem. Mater. Treat (Russ.) 4, 75 (1998).Google Scholar
13. Muller, K. A., Univerisitesforlaget, 61–96 (1971).Google Scholar
14. Kliava, J., EPR, Spectroscojy Disordered, Solids (Zinatne, Riga, 1988).Google Scholar
15. Fielding, P. E., White, T. J., J. Mat. Res. 2 (3) 387 (1987).Google Scholar
16. Iton, L. E., Brodbeck, C. M., Suib, S. L., Stucky, G. D., J. Chem. Phys. 79 (3) 1135 (1983).Google Scholar
17. Knyazev, O. A., Stefanovsky, S. V., Ioudintsev, S. V., Nikonov, B. S., Omelianenko, B. I., Mokhov, A. V., Yakushev, A. I., in Scientific Basis for Nucleair Watste Malnagemeniet XX, edited by Gray, W. J. and Triay, I. R. (Mat. Res. Soc. Symp. Proc. 465, Pittsburgh, PA, 1997) pp. 401–408.Google Scholar
18. Knyazev, O. A., Stefanovsky, S. V., ICEM'971nt. Conf, Sept. 11-16, 1997, p. 333, Singapore 1997.Google Scholar
19. Idenbom, V. L., Crystallography, 5, 115 (1960).Google Scholar
20. Coehlo, A. A., Cheary, R. W., Smith, K. L., J. Sol. State Chem. 129, 246 (1997).Google Scholar