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arXiv · 0803.3235

Strongly Correlated Electrons in the $[Ni(hmp)(ROH)X]_4$ Single Molecule Magnet: A DFT+U Study

Chao Cao·Stephen Hill·Hai-Ping Cheng
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Abstract

The single-molecule magnet $\mathrm{[Ni(hmp)(MeOH)Cl]_4}$ is studied using both density functional theory (DFT) and the DFT+U method, and the results are compared. By incorporating a Hubbard-U like term for both the nickel and oxygen atoms, the experimentally determined ground state is successfully obtained, and the exchange coupling constants derived from the DFT+U calculation agree with experiment very well. The results show that the nickel 3d and oxygen 2p electrons in this molecule are strongly correlated, and thus the inclusion of on-site Coulomb energies is crucial to obtaining the correct results.

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Chao Cao, Stephen Hill, Hai-Ping Cheng. 2008-03-21. Strongly Correlated Electrons in the $[Ni(hmp)(ROH)X]_4$ Single Molecule Magnet: A DFT+U Study. https://doi.org/10.1103/physrevlett.100.167206

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