The single-molecule magnet [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.
@article{arxiv.0803.3235,
title = {Strongly Correlated Electrons in the $[Ni(hmp)(ROH)X]_4$ Single Molecule Magnet: A DFT+U Study},
author = {Chao Cao and Stephen Hill and Hai-Ping Cheng},
journal= {arXiv preprint arXiv:0803.3235},
year = {2008}
}
Comments
4 pages, 5 figures, 2 tables. accepted by Phys. Rev. Lett