Vacancy formation energies in fcc metals: influence of exchange-correlation functionals and correction schemes
R. Nazarov, T. Hickel, J. Neugebauer.
Physical Review B, 85, 144118, (2012)
The performance of various exchange-correlation functionals (LDA, PBE, PW91, and AM05) in predicting vacancy formation energies has been evaluated for 12 fcc metals. A careful analysis of the results shows that differences between the theoretical result and experiment are mainly related to the way the various exchange correlation functionals describe the internal surface of the vacancy. Based on this insight we propose a modified version of the correction scheme of Mattsson,Wixom, and Armiento [Phys. Rev. B 77, 155211 (2008)]. Applying this approach to our results yields a perfect alignment of vacancy formation energies for all exchange-correlation functionals. These corrected values are also in very good agreement with the vacancy formation energies obtained in experiment.