Density functional theory in transition-metal chemistry: A self-consistent Hubbard U approach

Department of Materials Science and Engineering , Massachusetts Institute of Technology, Cambridge, Massachusetts, United States
Physical Review Letters (Impact Factor: 7.73). 10/2006; 97(10):103001. DOI: 10.1103/PhysRevLett.97.103001
Source: PubMed

ABSTRACT Transition-metal centers are the active sites for a broad variety of biological and inorganic chemical reactions. Notwithstanding this central importance, density-functional theory calculations based on generalized-gradient approximations often fail to describe energetics, multiplet structures, reaction barriers, and geometries around the active sites. We suggest here an alternative approach, derived from the Hubbard U correction to solid-state problems, that provides an excellent agreement with correlated-electron quantum chemistry calculations in test cases that range from the ground state of Fe2 and Fe2- to the addition elimination of molecular hydrogen on FeO+. The Hubbard U is determined with a novel self-consistent procedure based on a linear-response approach.

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