Orbital and dipolar contributions to the hyperfine fields in bulk bcc Fe, hcp Co, and at the Fe/Ag(100) interface: The inclusion of orbital polarization - art. no. 184413

First-principles calculations can make quantitative predictions of many pro perties of solids including magnetic hyperfine fields (B-hf). The inclusion of relativistic effects becomes important in this case. We have selected t o study three systems in order to assess the importance of orbital and dipo lar contributions to the B-hf and its anisotropies: bulk bcc Fe, hcp Co, an d the Fe/Ag(100) interface. For the last two, in-plane (parallel to the hex agonal planes and to the interface, respectively) and perpendicular magneti zations were considered. The influence of different exchange-correlation po tentials (local density and generalized: gradient approximation) and the in clusion of the orbital polarization term (known to improve the evaluation o f orbital moments) in the Hamiltonian is reported. A comparison is made wit h other theoretical studies and to experiment when possible.