Spin-dependent correlated atomic pseudopotentials

Abstract

The previously developed first-principles density-functional (nonlocal) atomic pseudopotentials are extended to include explicit spin effects as well as electronic correlation effects beyond the local-spin-density (LSD) formalism. Such angular-momentum-and spin-dependent pseudopotentials enable the extension of pseudopotential applications to study magnetic problems (e.g., transition-metal and other open-shell impurities in solids, ferromagnetic surfaces, etc.). As the spurious electronic self-interaction terms characterizing the LSD energy functional are self-consistently removed, these pseudopotentials can also be used to calculate reliably localized electronic states (e.g., deep defect levels, surface and interface states, narrow-band states in solids, etc.). Applications to atoms show that this pseudopotential method removes many of the anomalies of the LSD approach, including the systematically high total energy, the failure to predict the stability of negative ions, the lack of correlation between orbital energies and observed ionization potentials, and the erroneous ordering of $s$ and $d$ levels of the $3d$ transition elements Sc to Fe in their ${d}^{n\ensuremath{-}1}{s}^{1}$ configuration.