Estimation of Effective Parameters for the Transition-Metal Complexes by Mapping Self-Interaction Correction onto GGA+U

We propose a method to calculate the Hubbard U parameter in GGA+U or the α parameter in the atomic self-interaction correction (ASIC) scheme for transition-metald orbitals by mapping the self-interaction correction (SIC) onto GGA+U, which issuitable for atom-centered basis sets. SIC can offer a substitute for the HubbardU parameter in GGA+U, although its usage should be limited considering the differences between GGA+U and SIC. Approximations to reduce computational costfor self-interaction (SI) corrected localized orbitals are deduced from the propertiesof the unitary transformation in SIC and the atomic likeness of molecular orbitalsdominated by transition-metal d orbitals, and the parameters are obtained from theapproximate forms of the localized orbitals. First-row transition-metal complexeswere tested, and the results are comparable to experimental measurements and previous calculations. Our method does not guarantee better results than those ofthe linear response method or hybrid functionals, but mapping from SIC suppressesoverestimation of the U parameter to obtain proper geometries and energies for Feporphyrin-imidazole, Fe-porphyrin-CO and FeO2 modeling