Dresden 2026 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 3: Scanning probe techniques: Method development I
O 3.1: Vortrag
Montag, 9. März 2026, 10:30–10:45, HSZ/0204
Single-Molecule Insights into On-Surface C-C Bond Formation: Radical Control via Sequential Dehalogenation — Qigang Zhong1, Daniel Kohrs2, Jannis Jung3, Daniel Ebeling1, Doreen Mollenhauer3, Hermann Wegner2, and •Andre Schirmeisen1 — 1Institute of Applied Physics, Justus-Liebig University Giessen, Giessen, Germany — 2Institute of Organic Chemistry, Justus Liebig University Giessen, Giessen, Germany — 3Institute of Physical Chemistry, Justus Liebig University Giessen, Giessen, Germany
On-surface synthesis through dehalogenative coupling provides a powerful route to construct carbon-carbon bonds with atomic precision. Using a combination of scanning tunneling microscopy (STM), atomic force microscopy (AFM), and density functional theory (DFT), we investigated the radical intermediates and coupling pathways of brominated polyaromatic precursors, specifically BBPN and BPIN, on Ag(111). Controlled thermal and tip-induced dehalogenation enabled the selective generation of phenyl and naphthyl radicals, which were subsequently characterized at the single-molecule level. Statistical analysis of tip-induced reactions reveals that cyclization leading to C-C bond formation occurs preferentially when the first dehalogenation takes place at the naphthyl group. Computational modeling demonstrates that radical alignment and flexibility govern the feasibility of C-C coupling. These findings highlight the interplay between precursor structure, radical generation sequence, and surface interactions in steering on-surface coupling chemistry.
Keywords: on-surface synthesis; scanning probe manipulation