DFT with corrections for an efficient and accurate description of strong electron correlations in NiO
Julian Gebhardt, Christian Elsässer
Abstract
Abstract An efficient and accurate description of the electronic structure of a strongly correlated metal-oxide semiconductor like NiO has been notoriously difficult. Here, we study the capabilities and limitations of two frequently employed correction schemes, a DFT+ U on-site correction and a DFT+1/2 self-energy correction. While both methods individually are unable to provide satisfactory results, in combination they provide a very good description of all relevant physical quantities. Since both methods cope with different shortcomings of common density-functional theory (DFT) methods (using local-density or generalized-gradient approximations), their combination is not mutually dependent and remains broadly applicable. The combined approach retains the computational efficiency of DFT calculations while providing significantly improved predictive power.