A DFT+Nonhomogeneous DMFT approach for Finite Systems

Abstract: For reliable and efficient inclusion of electron-electron correlation effects in nanosystems we propose a combined density-functional-theory/nonhomogeneous dynamical-mean-field-theory (DFT + DMFT) approach which employs an approximate Iterative Perturbative Theory (IPT) impurity solver. The validity of the method is demonstrated by successful examination of the size-dependent magnetic properties of iron nanoparticles containing 11-100 atoms. We show that the DFT+ DMFT solution is in very good agreement with experimental data, in particular it does not lead to the overestimation of magnetization that is found with the DFT and DFT+U techniques. More importantly, we demonstrate that DFT+DMFT approach can be used for accurate and realistic description of nanosystems containing about hundred atoms.