Regensburg 2016 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 98: Organic-Inorganic Systems V: Adsorption on Metals

O 98.10: Vortrag

Freitag, 11. März 2016, 12:45–13:00, H24

Self-assembly of triphenylene molecules on the reconstructed Au(111) surface: influence of the surface stacking order — Sören Zint¹, •Daniel Ebeling¹, Sebastian Ahles², Hermann A. Wegner², and André Schirmeisen¹ — ¹Institute of Applied Physics (IAP), Justus Liebig University Giessen, Heinrich-Buff-Ring 16, 35392 Giessen, Germany — ²Institute of Organic Chemistry, Justus Liebig University Giessen, Heinrich-Buff-Ring 17, 35392 Giessen, Germany

Polycyclic aromatic hydrocarbons are an interesting component for the fabrication of nanoscale electronic devices, due to an extended pi-system and the possibility of forming graphene-like material. A powerful tool for the bottom-up fabrication of such nanostructures is molecular self-assembly. We study self-assembly of triphenylene molecules on the reconstructed Au(111) surface at submonolayer coverages by low temperature UHV STM at 5K. The molecules adsorb planarly, in two orientations only, corresponding to a 60° rotation. At low and medium coverages self-assembly is determined by strong attractive surface-molecule interactions and repulsive molecule-molecule interactions, which is accompanied by a one-to-one ratio of molecular orientations. At full monolayer coverage, however, the molecules undergo a reorientation into two different close-packed domains, leading to a significant overrepresentation of one molecular orientation. This reorientation strongly correlates with the stacking order of the substrate. Hence, the self-assembly process is controlled by the interaction of triphenylene with subsurface Au layers, which provides an additional mechanism for designing new systems.