Self-interaction-corrected pseudopotential scheme for magnetic and strongly-correlated systems

Local-spin-density-functional (LSDA) calculations may be affected by severe errors when applied to the study of magnetic and strongly correlated materials. Some of these faults can be traced back to the presence of the spurious self-interaction in the density functional. Since the application of a fully self-consistent self-interaction correction is highly demanding even for moderately large systems, we pursue a strategy of approximating the self-interaction-corrected potential with a nonlocal, pseudopotentiallike projector, first generated within the isolated atom and then updated during the self-consistent cycle in the crystal. This scheme, whose implementation is totally uncomplicated and particularly suited for the pseudopotental formalism, dramatically improves the LSDA results for a variety of compounds with a minimal increase of computing cost.