A first-principles study of Cr impurities in iron.

The first-principles molecular cluster discrete variational method (DV) is used to investigate the electronic structure and local magnetic properties of Cr impurities in bcc iron and Fe/Cr interfaces. The spin polarized case is considered within the framework of the local-spin-density approximation of the density function theory. The effect on the local moment and hyperfine magnetic field (Fermi contact term) of adding Cr atoms in the vicinity of Fe atoms is investigated. For a Cr impurity in bcc iron the calculated magnetic moment and hyperfine field is -0.62 mu(B) and -300 kG, respectively. For pure chromium we obtained -0.49 mu B and -67 kG. The Fe moment is sensitive to the separation between Cr atoms in the first shell of neighbors.