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Comment on “Band gap bowing and electron localization of GaXIn1-XN” [J. Appl. Phys. 100, 093717 (2006)]

Journal of Applied Physics (Impact Factor: 2.21). 01/2008; 103(9):096101-096101-3. DOI: 10.1063/1.2908179

ABSTRACT Some previous density functional theory (DFT) calculations of the band gap of wurtzite and cubic InN, before the work of Lee and Wang [J. Appl. Phys. 100, 093717 (2006)], are in agreement with the screened-exchange findings of these authors and with experiment. These previous findings point to an intrinsic capability of DFT, in the local density approximation, to correctly describe the band gap of semiconductors. These comments also discuss some recent results [Phys. Rev. B 76, 037101 (2007)] on an extensive hybridization of the In 4d and N 2s bands that is lost when the d electrons are included in the core. Our discussions in these comments indicate that when the two inherently coupled equations of DFT are both solved self-consistently, the resulting bands, including low-lying conduction ones, appear to have much more physics content than previously believed.

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