On the reorientation transition in Cu(100)/Ni n /H

Using the results of a previous study in terms of the scalar-relativistic full- potential linearized augmented-plane-wave method, the fully relativistic screened Korringa-Kohn-Rostoker approach is applied in order to describe the shift in the critical thickness for the so-called inverse reorientation transition from in plane to perpendicular in Ni films on Cu(100) upon loading with H. It is argued that, on average, by loading with H the interlayer distances in the Ni films would have to be reduced by about 3% or, expressed in absolute distances by about 0.05 A, compared with the bare systems, to cause the critical thickness to decrease from about 10 monolayers (ML) for the bare systems to about 8ML for completely H-covered Ni films. Calculations with statistically partial coverages with H and for a complete diffusion of H in the first Ni layer convincingly support this view.