| Abstract
| - The epitaxial monolayer of NiO on Pd(100) has been theoretically simulated using a hybrid-exchange GGA-DFT Hamiltonian and a slab model, periodic in two dimensions. This “perfect” system is an essential referencefor the simulation of nonstoichiometric two-dimensional phases which are formed during the deposition ofnickel on palladium in the presence of oxygen. The adequacy of the computational procedure is discussed,especially as concerns the use of a thermal smearing technique which has been adopted to improve theconvergence properties of the SCF procedure and to prevent the onset of nonphysical spin-polarized solutions.The equilibrium configuration corresponds to antiferromagnetic order in the overlayer, with oxygens on topof the surface Pd atoms; the ad-film is slightly corrugated with Ni closer to the surface by 0.1 Å with respectto O. The interaction energy is quite small, 0.20 eV/NiO unit (about 5 kcal mol-1); correspondingly, theelectronic and magnetic properties of the Pd slab and the isolated NiO monolayer are only marginally affectedby the interaction.
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