The method of low-energy ion scattering in the impact collision mode was substantially improved by the use of alkali ions. Alkali ions extend the capabilities of the impact collision mode technique towards the relative positioning of atoms lying in the first and deeper layers, which was a premise for the characterization of surface reconstruction. The self calibration procedure based on the experimental determination of an effective shadow cone was an important advantage. The small contribution of multiple scattering effects in impact collision mode permitted a straightforward determination of the locations of surface atoms. On the basis of a large number of impact collision mode data the oxygen induced surface reconstruction of Cu(110) was shown to be correctly described by the missing row model.

Determination of Surface Reconstruction with Impact-Collision Alkali Ion Scattering. H.Niehus, G.Comsa: Surface Science, 1984, 140[1], 18-30