Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-25T15:25:29.528Z Has data issue: false hasContentIssue false

Thermodynamic Properties of Actinide Oxide Solid Solutions

Published online by Cambridge University Press:  15 March 2011

Lindsay C. Shuller
Affiliation:
University of Michigan, Department of Materials Science and Engineering
Niravun Pavenayotin
Affiliation:
University of Michigan, Department of Nuclear Engineering and Radiological Sciences
Rodney C. Ewing
Affiliation:
University of Michigan, Department of Materials Science and Engineering University of Michigan, Department of Nuclear Engineering and Radiological Sciences University of Michigan, Department of Geological Sciences
Udo Becker
Affiliation:
University of Michigan, Department of Geological Sciences
Get access

Abstract

Density functional theory and Monte(Carlo methods were used to investigate the solid( solution behavior of actinide dioxides (AcO2). The end(members of interest include: ZrO2, ThO2, UO2, NpO2, and PuO2; all have the isometric fluorite structure. Ab initio and subsequent Monte( Carlo simulations are used to calculate the excess enthalpy of mixing (ΔHexcess), excess Gibbs free energy of mixing (ΔGexcess), and excess configurational entropy (ΔSexcess) for the above solid(solution series. From ΔGexcess, phase diagrams are derived and miscibility gaps identified. All of the binaries of the aforementioned end(members were studied; however, this paper focuses on the U1(xZrxO2 and Np1(xUxO2 binaries. About 25 at.% Zr can be in solid solution with the UO2 matrix above 1500 K, while Np is completely miscible in the UO2 matrix. Partial cation ordering was observed at all temperatures for the U1(xZrxO2 binary. The Np1(xUxO2 binary approaches perfect cation disorder at high temperatures (2000 K). The cation ordering scheme is not identified in this study because the number of cation(cation interaction parameters was limited by the single unit cell from the ab initio calculations.

Type
Research Article
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. Imura, A., Touran, N. and Ewing, R.C., Submitted to J. Nucl. Mater. (2008).Google Scholar
2. Morimoto, K., Kato, M., Ogasawara, M., Kashimura, M. and Abe, T., J. Alloy. Compd. 452, 54 (2008).Google Scholar
3. Arima, T., Yamasaki, S., Yamahira, K., Idemitsu, K., Inagaki, Y. and Degueldre, C., J. Nucl. Mater. 352, 309 (2006).Google Scholar
4. Sato, I., Furuya, H., Arima, T., Idemitsu, K. and Yamamoto, K, J. Nucl. Mater. 273, 239 (1999).Google Scholar
5. Sobolev, V., Lemehov, S., Messaoudi, N., Uffelen, P. Van and Abderrahim, H. Aït, J. Nucl. Mater. 319, 131 (2003).Google Scholar
6. Morss, L.R., J. Chem. Thermodyn. 34, 229 (2002).Google Scholar
7. Navrotsky, A., in Structure and Bonding in Crystals. Vol. II., edited by O'Keefe, M. and Navrotsky, A. (Academic Press, New York, 1981), pp. 7193.Google Scholar
8. Vinograd, V.L., Sluiter, M.H.F., Winkler, B., Putnis, A., Halenius, U., Gale, J.D. and Becker, U., Mineral. Mag. 68, 101 (2004).Google Scholar
9. Reich, M. and Becker, U., Chem. Geo. 225, 278 (2006).Google Scholar
10. Segall, M.C., Lindan, P.J.D., Probert, M.J., Pickard, C.J., Hasnip, P.J., Clark, S.J. and Payne, M.C., J. Phys-Condens. Mat. 14, 2717 (2002).Google Scholar
11. Perdew, J.P. and Wang, Y., Phys. Rev. B. 45, 13244 (1992).Google Scholar
12. Myers, E.R., Phys. Chem. Miner. 25, 465 (1998).Google Scholar
13. Yeomans, J.M., in Statistical Mechanics of Phase Transitions, (Oxford Science Publications, Clarendon Press, Oxford, 1992) p. 168.Google Scholar
14. Miwa, S., Osaka, M., Yoshimochi, H., Tanaka, K., Kurosaki, K., Uno, M. and Yamanaka, S., J. Alloy. Compd. 444–445, 610 (2007).Google Scholar