NITROGEN INDUCED NI(110)-(2X3) RECONSTRUCTION - A STRUCTURE DETERMINATION WITH ION-SCATTERING SPECTROSCOPY AND SCANNING-TUNNELING-MICROSCOPY

180-degrees low energy ion scattering spectroscopy in the impact collision mode with detection of noble gas neutrals (NICISS) shows that the nitrogen induced (2 X 3) structure on Ni(110) results from the reconstruction of the first Ni layer. The reconstruction can be described as a modified missing row structure with every third [110] row of the first layer of Ni atoms missing. The NICISS patterns imply that there is no measurable reconstruction of the Ni atoms in the [110] direction. The double periodicity in the [110] direction is probably due to the positions of the adsorbed nitrogen atoms. In another phase of the (2 X 3) superstructure some of the LEED reflexes are split. It was confirmed by STM investigation that the splitting is produced by the anti-phase boundaries of the (2 X 3) domains.