ELECTRONIC AND MAGNETIC-STRUCTURE OF (111) STACKING-FAULTS IN NICKEL

The electronic and magnetic structure of {111} stacking faults in nickel is investigated utilizing a fully self-consistent, layered multiple-scattering approach which does not require full three-dimensional symmetry or the use of finite-size slabs. The electronic and magnetic structures of a twin boundary, an intrinsic fault, an extrinsic fault, and two other stacking sequences are calculated. In addition, total energies of the faults are calculated and found to be in good agreement with the available experimental results. Localized states appear in all the studied stacking faults; the state's energies and exchange splittings are tabulated. The presence of a stacking fault results in a decrease in the spin polarization near the faults. This decrease arises from subtle changes in the electronic structure arising from the fault. For all the faults, the spin polarization is found to be insensitive to the orientation of the nearest-neighbor atoms, but instead can be related to the distance to the nearest atom in the direction perpendicular to the fault plane. Very simple empirical expressions for calculating the total energy and spin polarization of any stacking configuration are presented.