SURFACE-STRUCTURE OF CESIUM ADSORPTION ON THE SI(001) 2X1 SURFACE

The detailed surface structure of Cs adsorption on the Si(001) 2X1 sur face was investigated by means of tensor low-energy electron diffracti on analysis. Various adsorption sites were considered including the re cently proposed possibility of asymmetric dimer reconstruction of the Si top layer. We confirm the structure model with double-layer adsorba tes and symmetric Si dimers underneath for the saturation coverage Cs adsorption. The major structural parameters within this structure are discussed in terms of the covalent bonding between the adsorbates and Si surface atoms. [S0163-1829(98)06016-0].