Berlin 2015 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 41: Inorganic/Organic Interfaces
O 41.6: Poster
Dienstag, 17. März 2015, 18:15–21:00, Poster B
From hydrogen bonding to metal-coordination and back: porphyrin derivatives on Ag(111) — •Kathrin Müller1, Florian Studener1, Nicolas Marets2, Véronique Bulach2, Mir Wais Hosseini2, and Meike Stöhr1 — 1Zernike Institute for Advanced Materials, University of Groningen, The Netherlands — 2Laboratoire de Tectonique Moléculaire, Institut Le Bel, Université de Strasbourg, France
The formation of well-ordered molecular networks on surfaces has gained increasing attention over the last decades from a fundamental point of view as well as for their potential application in organic devices like organic photovoltaics or organic field effect transistors. In our studies we used a porphyrin derivative, which is functionalized at the meso positions with two pyridyl groups and two pentyl chains in trans configuration. We used scanning tunneling microscopy (STM) in order to investigate the self-assembly of this molecule on Ag(111). For submonolayer to monolayer coverage, a close-packed rhombic network is observed, which is stabilized via hydrogen bonding. Upon deposition of Co atoms, a porous hexagonal network forms by coordination of the pyridyl groups to the cobalt atoms. Upon thermal annealing at 450 K the hexagonal network is transformed into a second close-packed structure. We assign these structural changes to the Co-metalation of the porphyrin core. For an excess of Co atoms the porous hexagonal network is stable up to 600 K. These results are compared to a similar porphyrin derivative with a Ni core.