The magnetic anisotropy energy of Cu(100)/Ni/Co-m, 0 less than or equal to
m less than or equal to 5, is calculated using the spin-polarized fully rel
ativistic screened Korringa-Kohn-Rostoker method for layered systems. The N
i film was divided into two regions, one consisting of Ni layers epitaxiall
y grown on Cu(100) and tetragonally relaxed with a c/a ratio of 0.945 and,
subsequently a transient region subject of strain relaxation, the other one
consisting of Ni layers corresponding to a fee Ni parent lattice. For both
regions, separate calculations were performed and then combined with each
other on the basis of an analysis of layer decomposed contributions to the
anisotropy energy. By varying the thickness of both regions the critical (t
otal) thickness for the reorientation transition of the magnetization from
perpendicular to in-plane is determined. Capping the Ni film with Co is fou
nd to show an unexpected behavior: the number of Ni layers, at which the re
orientation occurs, is first increased until 2 ML of Co are added and then
decreases rapidly with the addition of more Co layers. This feature is main
ly attributed to changes in the band part of the anisotropy energy induced
by the Ni/Co interface as seen in terms of layer-resolved contributions.