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arXiv · 0806.1793

Ab initio investigation on oxygen defect clusters in UO2+x

Hua Y. Geng·Ying Chen·Yasunori Kaneta·Motoyasu Kinoshita
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Abstract

By first-principles LSDA+U calculations, we revealed that the current physical picture of defective uranium dioxide suggested solely by neutron diffraction analysis is unsatisfactory. An understanding based on quantum theory has been established as a thermodynamical competition among point defects and cuboctahedral cluster, which naturally interprets the puzzled origin of the asymmetric O' and O'' interstitials. It also gives a clear and consistent agreement with most available experimental data. Unfortunately, the observed high occupation of O'' site cannot be accounted for in this picture and is still a challenge for theoretical simulations.

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Hua Y. Geng, Ying Chen, Yasunori Kaneta, Motoyasu Kinoshita. 2008-07-11. Ab initio investigation on oxygen defect clusters in UO2+x. https://doi.org/10.1063/1.3035846

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