Dresden 2017 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 38: Organic-Inorganic Hybrid Systems and Organic Films V
O 38.5: Vortrag
Dienstag, 21. März 2017, 15:15–15:30, WIL A317
Understanding the planarization of shuttle-cock shaped subphthalocyanine molecule on Cu(111) surface — •Shashank S. Harivyasi1, Oliver T. Hofmann1, Nahid Ilyas2, Oliver L.A. Monti2, and Egbert Zojer1 — 1Institute of Solid State Physics, NAWI Graz, Graz University of Technology, Austria — 2University of Arizona, Tucson, Department of Chemistry & Biochemistry, 1306 E. University Blvd., Tucson, AZ 85721, USA
The structure of an organic semiconductor plays a determining role in its adsorption on a metal surface. Large planar molecules like planar phthalocyanines, pentacene and PTCDA typically lie completely flat on most metal surfaces. The situation becomes more complex in case of non-planar molecules. They generally show a tendency to planarize upon adsorption but the extent of this planarization varies from negligible to almost complete for various metal-molecule combinations.
Here, we try to understand the reasons for this planarization by studying an extreme example exhibiting almost complete planarization: adsorption of shuttle-cock shaped Chloroboron subphthalocyanine on Cu (111). Using DFT, we study the steps of the adsorption process by gradually increasing the van der Waals interaction between the adsorbate and the substrate and following the evolution of the molecule's electronic and geometrical structure. We identify the bonding of the molecule as a two-stage process involving Fermi-level pinning followed by a rehybridization of the molecule's frontier orbitals. Especially the observed evolution of charge rearrangements help us to explain why we see an almost complete planarization.