Flores, M.A.Orellana, W.Menéndez-Proupin, E.2019-12-112019-12-112018-10Physical Review B, 98(15), art. no. 155131.2469-9950DOI: 10.1103/PhysRevB.98.155131http://repositorio.unab.cl/xmlui/handle/ria/11378Indexación: Scopus.This paper was supported by the Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT, Chile) under Grants No. 1170480 (W.O.) and No. 1171807 (M.A.F. and E.M-P.). Powered@NLHPC: This research was partially supported by the supercomputing infrastructure of the NLHPC (ECM-02).Hybrid functionals, which mix a fraction of Hartree-Fock exchange with local or semilocal exchange, have become increasingly popular in quantum chemistry and computational materials science. Here, we assess the accuracy of the Heyd-Scuseria-Ernzerhof (HSE) hybrid functional to describe many-electron interactions and charge localization in semiconductors. We perform diffusion quantum Monte Carlo calculations to obtain the accurate ground-state spin densities of the negatively charged (SiV)- and the neutral (SiV)0 silicon-vacancy center in diamond and of the cubic silicon carbide (3C-SiC) with an extra electron. We compare our diffusion quantum Monte Carlo results with those obtained with the HSE functional and find a good agreement between the two methods for (SiV)- and (SiV)0, whereas the correct description of 3C-SiC with an extra electron crucially depends on the amount of Hartree-Fock exchange included in the functional. Also, we examine the case of the neutral Cd vacancy in CdTe, for which we assess the performance of HSE versus the many-body GW approximation for the description of the position of the defect states in the band gap. © 2018 American Physical Society.enArtículo