Electronic structure of magnetic impurities calculated from first principles

The electronic structure of magnetic $3d$ impurities in Cu and Ag is calculated self-consistently from first principles. Using the density functional theory the exchange and correlation is treated in the local spin-density approximation of von Barth and Hedin. Our method is based on the Kohn-Korringa-Rostocker Green's-function method and the impurity is described by a single perturbed muffin-tin potential in an otherwise periodic lattice. We give results for the local density of states, the magnetic moments, and the phase shifts at the Fermi energy for the $3d$ impurities in Cu and Ag. Our results are in qualitative agreement with the Anderson model, however modifications due to the host band structure are important, especially for Mn and Fe in Cu. For all cases studied, the exchange integral $I$ lies between 0.65 and 0.8 eV.