General-potential study of the electronic and magnetic structure of FeCo

Full-potential calculations of the structural, electronic, and magnetic properties of B2 iron-cobalt are presented. The calculated spin- and charge-density anisotropies are compared to results from neutron-scattering experiments as well as to results from an earlier calculation employing spherical approximations. It is found that the elimination of shape approximations improves agreement with measured anisotropies, but significant discrepancies remain. These discrepancies are attributed to the local-spin-density approximation (LSDA). No significant improvement in the anisotropies is found when the LSDA is replaced by a generalized-gradient-approximation density functional.