Surface and subsurface distortions of the Au{110}-(1x2) structure

The reconstruction of the Au{110}-(1x2) missing-row surface has been studied by means of the new scattering and recoiling imaging spectrometry (SARIS) technique. The three-dimensional focusing patterns observed for scattering of 4 keV He+, Ne+ and Ar+ ions are highly sensitive to the structure of both the surface and subsurface layers. Classical ion trajectory simulations using the scattering and recoiling imaging code (SARIC) were used to simulate the scattering patterns. Using an R-Factor comparison of the experimental and simulated images, it is demonstrated that SARIS is sensitive to changes of the order of 0.02 Angstrom in the structural parameters of this Au surface. These parameters involve interlayer spacings, row pairing and row buckling in the first-through fifth atomic layers. Results for the shallow surface layers are in general agreement with the those of previous studies. The new results include structural parameters for the deeper subsurface layers and the observation of an oscillatory behavior of the layer spacings which is damped towards deeper layers. (C) 1998 Elsevier Science B.V.