Structure analysis of an oxidized nickel (110) surface using low energy ion scattering

Low energy (6 keV) argon and neon ion scattering in the low angle mode (θ = 30°) has been used to investigate changes in the surface structure of a Ni(110) surface caused by the adsorption of oxygen at low exposures (10^?6 Torr s). The experimental energy spectra indicate that due to adsorption of oxygen, the interatomic distance in the 〈1̄10〉 direction increases while in the 〈001̄〉 direction this distance seems to decrease. This represents strong evidence that a reconstruction process is taking place during the early stages of oxidation of the Ni(110) face, in which the interatomic distances in the 〈1̄10〉 direction doubles. The oxygen atoms were found to lie in or close to the nickel 〈001̄〉 rows. These results are not in agreement with recently published dynamical LEED calculations.