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arXiv · 1311.3147

A DFT+Nonhomogeneous DMFT approach for Finite Systems

Alamgir Kabir·Volodymyr Turkowski·Talat S. Rahman
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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.

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Alamgir Kabir, Volodymyr Turkowski, Talat S. Rahman. 2013-11-13. A DFT+Nonhomogeneous DMFT approach for Finite Systems. https://arxiv.org/abs/1311.3147

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