Photoelectrons spectroscopy of organised organic thin films

Low energy electron photoemission spectroscopy (LEPS) allows the study of the electronic properties of organized organic thin films (OOTF) adsorbed on conducting surfaces by monitoring the energy and angular distribution of electrons emitted from the substrate and transmitted through the film. This technique provides unique information on the electronic properties of the adsorbed layer. The electron transmission properties are explained by electronic band structure in the organic film. This band is an example of an electron resonance that is delocalized in the layer. It results from the two dimensional nature of the layer. Other resonances in the transmission spectra are also discussed, as well as their experimental manifestation. Despite the fact that the molecules in the OOTF are weakly interacting, when not charged, the electron transmission through the film is governed by cooperative effects. These effects must be taken into account when considering electronic properties of adsorbed layers.