The Structure of K-Monolayers and Cs-Monolayers on Cu(001) - Diffraction Experiments Far from the Bragg Point
Physica B 198(1-3): 66-69
The intensity analysis along the crystal truncation rods has been used to analyse in situ the adsorption behaviour and the structure of K and Cs on Cu(001) at submonolayer coverages and room temperature. Up to about 0.25 M L K atoms adsorb in hollow sites followed by formation of a quasihexagonal superstructure. In contrast, for Cs adsorption the data can be interpreted by the formation of quasihexagonal Cs islands that grow with increasing coverage. For K an effective radius of 1.6(1) angstrom independent of coverage is determined. For Cs we find d(perpendicular-to) = 2.1(1) angstrom after formation of the quasihexagonal superstructure.