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 Publish in OALib Journal ISSN: 2333-9721 APC: Only $99  Views Downloads  Relative Articles On the accuracy of commonly used density functional approximations in determining the elastic constants of insulators and semiconductors On the Locality of Physics in Metals, Semiconductors, and Insulators Photoproduction of iodine with nanoparticulate semiconductors and insulators Hybrid functionals for solids with an optimized Hartree-Fock mixing parameter Prediction of weak topological insulators in layered semiconductors Color centers in NaCl by hybrid functionals Band model for the understanding of ferromagnetism in semiconductors and insulators Hybrid functionals within the all-electron FLAPW method: implementation and applications of PBE0 Temperature dependence of the electronic structure of semiconductors and insulators Hybrid inverse problems and internal functionals More... Physics 2011 # Comparative study of hybrid functionals applied to structural and electronic properties of semiconductors and insulators  Full-Text Cite this paper Abstract: We present a systematic study that clarifies validity and limitation of current hybrid functionals in density functional theory for structural and electronic properties of various semiconductors and insulators. The three hybrid functionals, PBE0 by Perdew, Ernzerhof, and Becke, HSE by Heyd, Sucseria, and Ernzerhof, and a long-range corrected (LC) functional, are implemented in a well-established plane-wave-basis-set scheme combined with norm-conserving pseudopotentials, thus enabling us to assess applicability of each functional on equal footing to the properties of the materials. The materials we have examined in this paper range from covalent to ionic materials as well as a rare-gas solid whose energy gaps determined by experiments are in the range of 0.6 eV - 14.2 eV: i.e., Ge, Si, BaTiO$_3$,$\beta\$-GaN, diamond, MgO, NaCl, LiCl, Kr, and LiF. We find that the calculated bulk moduli by the hybrid functionals show better agreement with the experiments than the generalized gradient approximation (GGA) provides, whereas the calculated lattice constants by the hybrid functionals and GGA show comparable accuracy. The calculated energy band gaps and the valence-band widths for the ten prototype materials show substantial improvement using the hybrid functional compared with GGA. In particular, it is found that the band gaps of the ionic materials as well as the rare-gas solid are well reproduced by the LC-hybrid functional, whereas those of covalent materials are well described by the HSE functional. We also examine exchange effects due to short-range and long-range components of the Coulomb interaction and propose an optimum recipe to the short-range and long-range separation in treating the exchange energy.

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