Electron transmission through organized organic thin films studied by discrete initial electron kinetic energies

Synchrotron radiation (SR) pulses are used to eject electrons from a gold s ubstrate covered with organized organic thin films (OOTF) in order to inves tigate their transmission probability through the OOTF as a function of the electron initial kinetic energy. By variation of the SR photon energy with in a few eV above the Au-4f binding energy levels we controlled the initial kinetic energy of the substrate electrons. The observed oscillations in th e transmission probability for porphyrin-based films as a function of the k inetic energy is argued to be due to effects of band structure above the va cuum level in the well-ordered molecular adsorbate. We also present valence photoemission spectra (PES) of different type OOTF and demonstrate how the ir coverage of the substrate affects the PES.