Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 8: Surface Reactions
O 8.2: Vortrag
Montag, 18. März 2024, 10:45–11:00, MA 141
On-Surface Isomerization of Indigo within 1D Coordination Polymers — •Hongxiang Xu1, Ritam Chakraborty2, Abhishek Kumar Adak2, Arpan Das2, Biao Yang1, Dennis Meier1, Alexander Riss1, Joachim Reichert1, Shobhana Narasimhan2, Johannes V. Barth1, and Anthoula C. Papageorgiou1,3 — 1Technische Universität München, Germany — 2Jawaharlal Nehru Centre for Advanced Scientific Research, India — 3National and Kapodistrian University of Athens, Greece
We present surface-confined metallosupramolecular engineering of coordination polymers using natural dyes as molecular building blocks: indigo and the related Tyrian purple. Both building blocks yield identical, well-defined coordination polymers composed of (1 dehydroindigo : 1 Fe) repeat units on two different silver single crystal surfaces. These polymers are characterized atomically by submolecular resolution scanning tunneling microscopy, bond-resolving atomic force microscopy and X-ray photoelectron spectroscopy. On Ag(100) and on Ag(111), the trans configuration of dehydroindigo results in N,O-chelation in the polymer chains. On the more inert Ag(111) surface, the molecules undergo thermally induced isomerization from the trans to the cis configuration and afford N,N- plus O,O-chelation. Density functional theory calculations confirm that the coordination polymers of the cis-isomers on Ag(111) and of the trans-isomers on Ag(100) are energetically favored. Our results demonstrate post-synthetic linker isomerization in interfacial metal-organic nanosystems.
Keywords: Indigo; Isomerization; Coordination polymer; Scanning tunneling microscopy; Bond-resolving atomic force microscopy