Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...

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

O: Fachverband Oberflächenphysik

O 7: Focus Session: Functional Molecules at Surfaces I

O 7.6: Vortrag

Montag, 16. März 2020, 12:00–12:15, TRE Ma

UV-light assisted on-surface synthesis of polyphenyl chains — •Kathrin Schneider, Jacques Bonvoisin, and Veronique Langlais — Center of Materials Elaboration and Structural Studies (CEMES) -CNRS, 29 rue Jeanne Marvig, 31055 Toulouse, France

On surface synthesis is a powerful tool to create extended molecular structures directly on a surface such as molecular chains or networks, not synthesizable in solution. In order to get a detailed understanding of the reaction steps and to optimize the reaction parameters, we studied commercial diiodo-p-ter-phenyl as model molecules.

These iodine functionalized molecules should react between them by losing their halogen and by creating C-C bonds upon Ullmann coupling. Scanning Tunneling Microscopy and Spectroscopy (STM and STS) were used to study them on Ag(001) surface, acting as substrate and catalyst. Carbon-iodine bond dissociation energy was determined by bond cleavage with the STM tip. Unreacted molecules forming a self-assembly monolayer convert, depending on annealing temperature, into organometallic and finally to fully polymerized molecular chains. The reaction temperature could clearly be reduced by using UV-light in addition to thermal treatment. These results open the route for on-surface synthesis dealing with larger or more fragile molecules.