STRUCTURE OF AU ON AG(110) STUDIED BY SCANNING-TUNNELING-MICROSCOPY

The epitaxial growth of Au on Ag(110) has been studied by scanning tun neling microscopy up to 8 ML. In the submonolayer range the results sh ow that gold atoms are intermixed with the silver atoms in the top two layers. Above 1 ML a two-dimensional fingerlike growth gives rise to anisotropic three-dimensional islands of gold, which appear to be ther mal equilibrium structures. Above 5 ML, the gold overlayer forms a (1 X 3) reconstruction which is manifested as double rows of atoms growin g along [110BAR]. The development of this reconstruction is followed a s a function of coverage.