Large effects of subtle electronic correlations on the energetics of vacancies in α-Fe

Pascal Delange (1) , Thomas Ayral (2) , Sergei Simak , Michel Ferrero (1, 3, 4) , Olivier Parcollet (2) , Silke Biermann (1) , Leonid Pourovskii (1, 5)

1 CPHT - Centre de Physique Théorique [Palaiseau]
2 IPHT - Institut de Physique Théorique - UMR CNRS 3681
3 CNRS - Centre National de la Recherche Scientifique
4 CdF (institution) - Collège de France
5 LIU - Linköping University

We study the effect of electronic Coulomb correlations on the vacancy formation energy in para-magnetic α-Fe within ab initio dynamical mean-field theory. The calculated value for the formation energy is substantially lower than in standard density-functional calculations and in excellent agreement with experiment. The reduction is caused by an enhancement of electronic correlations at the nearest neighbors of the vacancy. This effect is explained by subtle changes in the corresponding spectral function of the d-electrons. The local lattice relaxations around the vacancy are substantially increased by many-body effects.

Domaines: Physique [physics]

Pascal Delange, Thomas Ayral, Sergei Simak, Michel Ferrero, Olivier Parcollet, et al.. Large effects of subtle electronic correlations on the energetics of vacancies in α-Fe. Physical Review B, 2016, 94 (10), pp.100102. ⟨10.1103/PhysRevB.94.100102⟩. ⟨cea-01341606⟩