Electronic and magnetic properties of Fe_xNi_1-xoverlayer alloys on W(110) substrate: Ab initio study

Structural, electronic and magnetic properties for Fe x Ni 1-x monolayer alloys on W(110) have been investigated, by considering the different size effect, using Density Functional Theory (DFT) calculations within the pseudopotential plane wave basis set method, including generalized gradient approximation (GGA) as the exchange-correlation potential . An antiferromagnetic coupling is found between Fe and Ni (W) atoms, when x coverage varying from 0.17 to 0.67, while for x ranging from 0.67 to 0.83 a ferromagnetic (antiferromagnetic) coupling is obtained between Fe and Ni (W). Consequently, the phase transition between the FM and AF occurs at x = 0.67 coverage. The interactions of the deposited monolayer alloy with the W substrate have led to a significant depreciation of the magnetic moments of Ni atoms, for all concentrations. A surface ripple is also shown with an inward (outward) relaxation for Ni (Fe) positions from the W subsurface layer.