Photoelectron and Absorption Spectroscopy Studies of Metal-Free Phthalocyanine on Au(111): Experiment and Theory
Résumé
The adsorption of monolayers and multilayers of metal-free phthalocyanine molecules on the Au(111) (root 3 x 22) reconstructed surface has been investigated by X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). Our results for the monolayer show that the molecules are arranged tightly onto the surface with their molecular plane parallel to it. In addition, the X-ray absorption spectra of the monolayer have been modeled by density functional theory, which could enlighten new aspect of the interaction between molecules and substrate. The XAS results evidence that also in the multilayer the molecules keep the orientation with the molecular plane parallel to the surface. These results are discussed in the framework of moleculemolecule/moleculeadsorbate interactions.