Regensburg 2010 – wissenschaftliches Programm
O 47.7: Vortrag
Mittwoch, 24. März 2010, 12:00–12:15, H36
Effect of fluorination on the adsorption geometry and electronic structure of Zn-phthalocyanine molecules — •A. Gerlach1, T. Hosokai1, F. Schreiber1, S. Duhm2, N. Koch2, H. Yamane3, Y. Tanaka3, Y. Mi4, and J. Zegenhagen.4 — 1Institut für Angewandte Physik, Universität Tübingen, Tübingen, Germany — 2Institut für Physik, Humboldt-Universität, Berlin, Germany — 3Institute for Molecular Science, Okazaki, Japan — 4European Synchrotron Radiation Facility, Grenoble, France
Using the X-ray standing wave (XSW) technique and angle-resolved UPS (ARUPS) we studied the structural and electronic properties of Zn-phthalocyanine (ZnPc) and perflurinated Zn-phthalocyanine (F16ZnPc) molecules on Cu(111).
The element specific bonding distances of ZnPc and F16ZnPc derived by XSW show that the molecule-substrate interaction depends significantly on the chemical structure of the adsorbate. Compared to its perfuorinated derivative ZnPc shows a surprisingly small bonding distance (d(C)=2.49 Å), which reflects the strong interaction of the molecules with the copper substrate. Moreover, the XSW data reveal different distortions of these molecules that can be related to their specific bonding mechanism: Relative to the molecular plane the central zinc atom of ZnPc is pulled 0.25 Å towards the substrate, whereas the fluorine atoms of F16ZnPc are pushed 0.15 Å towards the vacuum side. We show that these adsorption induced changes of the molecular geometry are reflected in electronic structure of both systems.