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arXiv · 1202.5030

First-principles calculations of the electronic structure of open-shell condensed matter systems

Johannes Lischner·Jack Deslippe·Manish Jain·Steven G. Louie
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Abstract

We develop a Green's function approach to quasiparticle excitations of open-shell systems within the GW approximation. It is shown that accurate calculations of the characteristic multiplet structure require a precise knowledge of the self energy and, in particular, its poles. We achieve this by constructing the self energy from appropriately chosen mean-field theories on a fine frequency grid. We apply our method to a two-site Hubbard model, several molecules and the negatively charged nitrogen-vacancy defect in diamond, and obtain good agreement with experiment and other high-level theories.

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Johannes Lischner, Jack Deslippe, Manish Jain, Steven G. Louie. 2012-02-22. First-principles calculations of the electronic structure of open-shell condensed matter systems. https://doi.org/10.1103/physrevlett.109.036406

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