Abstract
The density functional theory (DFT)+U method is an efficient and effective way to calculate the ground-state properties of strongly correlated transition metal compounds, with the effective U parameters typically determined empirically. Two ab initio methods have been developed to compute the U parameter based on either constrained DFT (CDFT) or unrestricted Hartree-Fock (UHF) theory. Previous studies have demonstrated the success of both methods in typical open-shell materials such as FeO and NiO. In this Communication we report numerical instability issues that arise for the CDFT method when applied to closed-shell transition metals, by using ZnO and Cu2O as examples. By contrast, the UHF method behaves much more robustly for both closed- and open-shell materials, making it more suitable for treating closed-shell transition metals, as well as main group elements.
Original language | English (US) |
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Article number | 121105 |
Journal | Journal of Chemical Physics |
Volume | 140 |
Issue number | 12 |
DOIs | |
State | Published - Mar 28 2014 |
All Science Journal Classification (ASJC) codes
- General Physics and Astronomy
- Physical and Theoretical Chemistry