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

Heather J. Kulik·Matteo Cococcioni·Damian A. Scherlis·Nicola Marzari
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Abstract

Transition-metal centers are the active sites for many 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 Fe$_2$ and Fe$_2^-$ 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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Heather J. Kulik, Matteo Cococcioni, Damian A. Scherlis, Nicola Marzari. 2006-08-12. Density functional theory in transition-metal chemistry: a self-consistent Hubbard U approach. https://doi.org/10.1103/physrevlett.97.103001

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