The 180° enhancement of the ion backscattering surface peak yield from near (110)Au

Abstract The enhancement in ion backscattering surface peak yield at 180° has been measured for 0.5 MeV and 1.0 MeV He + incident upon the 〈110〉 and 〈112〉 directions of a near (110)Au single crystal at 40 K, 170 K, and 300 K. The normal (RBS) surface peak yield observed at 150° is in agreement with that calculated by computer simulation using a modified 1 × 2 surface structure for (110)Au, including the effects of enhanced vibrations in the surface layers and vibration correlations. A theoretical description of the enhanced yield at 180°, based on a two-atom scattering model, is given. The theoretical enhancement from a 1 × 2 surface is in good agreement with the observations.