Comment on Interplay of defect cluster and the stability of xenon in uranium dioxide from density functional calculations

Geng et al. [H. Y. Geng, Y. Chen, Y. Kaneta, M. Kinoshita, and Q. Wu, Phys. Rev. B 82, 094106 (2010)] recently reported DFT + U calculations of xenon behavior in uranium dioxide UO(2). One of the main conclusions of their work is that the quasiannealing (QA) procedure allowed them to avoid metastable states created by the DFT + U approximation. However, based on a comparison of total energies, they stated that an incomplete implementation of occupation matrix control (OMC) had been done in our previous work [B. Dorado, G. Jomard, M. Freyss, and M. Bertolus, Phys. Rev. B 82, 035114 (2010)] and that we failed to reach the ground state of the perfect UO(2) fluorite structure. In this Comment, we show that the discrepancy they observed does not stem from an incomplete implementation of OMC, but from the calculation of the compensation charge used in the projector augmented-wave formalism.