Eur. Phys. J. B (2013) 86: 179
https://doi.org/10.1140/epjb/e2013-31047-y

Regular Article

First principle study of the behavior of helium in plutonium dioxide

¹ The College of Nuclear Technology and Automation Engineering, Chengdu University of Technology, Chengdu 610059, P.R. China
² Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610059, P.R. China
³ The National Key Laboratory of Nuclear Fuel and Materials, Nuclear Power Institute of China, Chengdu 610059, P.R. China

^a e-mail: txf8378@163.com

Received: 15 November 2012
Received in final form: 30 January 2013
Published online: 22 April 2013

Abstract

The incorporation and solution of helium in plutonium dioxide have been investigated based on density functional theory. The GGA and GGA + U approximations were used with the projector-augmented-wave method. Several defects that are likely to accommodate the incorporation of helium in PuO₂, such as oxygen vacancy, plutonium vacancy, divacancy and Schotty defects were considered in this work. With GGA approach, the lowest incorporation energy corresponds to neutral trivacancy, followed by divacancy and plutonium vacancy, while the GGA + U scheme gave us that oxygen vacancy is the most favorable incorporation site for He. Both SP-GGA and SP-GGA + U methods obtained a same conclusion that the most favorable solution site for He is oxygen vacancy, interstitial site and plutonium vacancy for under-, perfect and over-stoichiometry, respectively. Additionally, the concentrations of the point defects and the solution energy of He for the different incorporation sites as a function of the stoichiometry were also obtained based on the point-defect model.