Study of the C2H4/Si(100)-(2x1) interface by derivative photoelectron holography

The k derivative spectra (KDS) transform is used for construction of the three-dimensional atomic structure of the C2H4/Si(100)-(2 x 1) system from photoelectron diffraction data. The image function obtained by the KDS transform clearly observes the second-layer Si atoms and the C emitters apart from the first-layer Si atoms. The observations of the second-layer Si atoms and the C emitters make it easy to measure the C-C bond length correctly. Then a conclusive adsorption model - the di-sigma model - for the C2H4/Si(100)-(2 x 1) system is established. In comparison with the KDS transform, the normal small-cone transform hardly measures the C-C bond length. The ability to observe more scatterers of a photoelectron emitter by the KDS transform expands the applicability of holographic imaging.