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arXiv · 0804.0792

Correlation effects in the electronic structure of Mn$_4$ molecular magnet

D. W. Boukhvalov·L. I. Vergara·V. V. Dobrovitski·M. I. Katsnelson·A. I. Lichtenstein·P. Kögerler·J. L. Musfeldt·B. N. Harmon
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Abstract

We present joint theoretical-experimental study of the correlation effects in the electronic structure of (pyH)$_3$[Mn$_4$O$_3$Cl$_7$(OAc)$_3$]$\cdot$2MeCN molecular magnet (Mn$_4$). Describing the many-body effects by cluster dynamical mean-field theory, we find that Mn$_4$ is predominantly Hubbard insulator with strong electron correlations. The calculated electron gap (1.8 eV) agrees well with the results of optical conductivity measurements, while other methods, which neglect many-body effects or treat them in a simplified manner, do not provide such an agreement. Strong electron correlations in Mn$_4$ may have important implications for possible future applications.

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D. W. Boukhvalov, L. I. Vergara, V. V. Dobrovitski, M. I. Katsnelson, A. I. Lichtenstein, P. Kögerler, J. L. Musfeldt, B. N. Harmon. 2008-04-04. Correlation effects in the electronic structure of Mn$_4$ molecular magnet. https://doi.org/10.1103/physrevb.77.180402

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