The thesis presents fundamental studies of phthalocyanines (Pc), a group of organic macro-cycle molecules, similar to systems found in nature. The use of phthalocyanine molecular films in devices with a variety of possible technological applications has been the reason of the many studies during the last decades. Core and valence photoelectron spectroscopies (PES), X-ray absorption spectroscopy (XAS) and scanning tunneling microscopy (STM) techniques are used to study Pc molecules in gas phase and adsorbed on gold Au(111) and silicon Si(100)-2x1 substrates. Density function theory (DFT) is used to obtain further insights in the electronic structure of the phthalocyanines.We aim to obtain a deeper understanding of the molecule-molecule and molecule-substrate interactions, a fundamental requirement for improving devices based on organic materials. Gas phase PES experiments and DFT calculations performed on different Pcs show the influence of the metal atom on the valence band spectra, where FePc and H2Pc HOMO is formed from C2p states, whereas MnPc has mainly Mn3d character.PES and STM studies of H2Pc and LuPc2 on Au(111) show a formation of a monolayer for H2Pc and a bi-layer of LuPc2 at lower thicknesses. XAS studies show a parallel to surface orientation of both H2Pc and LuPc2 with a change in tilt angle of the molecules with increasing thickness.A comparison of LuPc2 adsorbed on pristine and passivated Si surfaces show a bulk-like LuPc2 character on passivated Si, whereas a surface induced difference in adsorption geometry is evidenced on pristine Si and two energetically different adsorption geometries are proposed.
| Identifer | oai:union.ndltd.org:CCSD/oai:tel.archives-ouvertes.fr:tel-01020786 |
| Date | 14 March 2014 |
| Creators | Bidermane, Ieva |
| Publisher | Université Pierre et Marie Curie - Paris VI |
| Source Sets | CCSD theses-EN-ligne, France |
| Language | English |
| Detected Language | English |
| Type | PhD thesis |
Page generated in 0.002 seconds