ROTATIONAL EPITAXY VS MISSING-ROW RECONSTRUCTION - AU CU/AU(110)/

From scanning tunneling microscopy and ion scattering spectroscopy, it is found that Cu deposition on Au(110)-(1 x 2) at 300 K leads to a sa ndwich structure with Cu atoms occupying sites in the second layer and Au atoms on top. At around theta(Ca) = 1.3 ML a new, stable phase wit h s-shaped chains of Au atoms in the surface layer, slightly rotated w ith respect to [1(1) over bar0$], is formed. This phase can be conside red as a case of rotational epitaxy on the strongly anisotropic fcc(11 0) surface. Energetic contributions responsible for its formation are discussed. (C) 1997 Elsevier Science B.V.