Berlin 2012 – wissenschaftliches Programm

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

O: Fachverband Oberflächenphysik

O 30: Focussed session: Functional molecules at surfaces I

O 30.3: Topical Talk

Dienstag, 27. März 2012, 11:15–11:45, A 053

How metal surfaces control adsorbate functionality: cooperativity, adatoms, and substrate interactions — •Felix Hanke — University of Liverpool, Liverpool, UK

Achieving complete atomic-level control and understanding of functional nanostructures in contact with a metal surface is one of the outstanding challenges in surface science. One of the most interesting issues is the role of the surface in driving the function and assembly of adsorbates and molecular switches. Here I will outline the impact and control of substrate reactivity and adatom incorporation on different molecular systems. These theoretical concepts will be illustrated in detail for two systems using van der Waals density functional theory calculations and STM simulations. First, the assembly of single porphyrins on Cu(110) leads to highly oriented one-dimensional nanostructures despite the complete lack of functionality to direct the self-assembly [1]. The porphyrin macrocycles are coupled by covalent C-Cu-C bonds, which result from the incorporation of adatoms into the structure. The one-dimensional nature of the chains is inherited from the substrate structure. Second, the recent synthesis of graphene nanoribbons (GNR) on the Au(111) surface will be discussed [2]. Again, the substrate plays a fundamental role in catalyzing the coupling reactions from a polyanthracene precursor to the full GNR. Successive couplings start at one end of the precursor and proceed cooperatively through the molecule in a domino-like fashion [3].

[1]J. Am. Chem. Soc. 133 12031 (2011); ACS Nano 5 9093 (2011); [2] Nature 466 470 (2010); [3] J. Am. Chem. Soc. 133 14884 (2011)