Surface-assisted dehydrogenative homocoupling of porphine molecules

Alissa Wiengarten, Knud Seufert, Willi Auwärter, David Ecija, Katharina Diller, Francesco Allegretti, Felix Bischoff, Sybille Fischer, David A. Duncan, Anthoula C. Papageorgiou, Florian Klappenberger, Robert G. Acres, Thien H. Ngo, Johannes V. Barth

Research output: Contribution to journalArticlepeer-review

128 Scopus citations

Abstract

The templated synthesis of porphyrin dimers, oligomers, and tapes has recently attracted considerable interest. Here, we introduce a clean, temperature-induced covalent dehydrogenative coupling mechanism between unsubstituted free-base porphine units yielding dimers, trimers, and larger oligomers directly on a Ag(111) support under ultrahigh-vacuum conditions. Our multitechnique approach, including scanning tunneling microscopy, near-edge X-ray absorption fine structure and photoelectron spectroscopy complemented by theoretical modeling, allows a comprehensive characterization of the resulting nanostructures and sheds light on the coupling mechanism. We identify distinct coupling motifs and report a decrease of the electronic gap and a modification of the frontier orbitals directly associated with the formation of triply fused dimeric species. This new on-surface homocoupling protocol yields covalent porphyrin nanostructures addressable with submolecular resolution and provides prospective model systems towards the exploration of extended oligomers with tailored chemical and physical properties.

Original languageEnglish
Pages (from-to)9346-9354
Number of pages9
JournalJournal of the American Chemical Society
Volume136
Issue number26
DOIs
StatePublished - 2 Jul 2014

Fingerprint

Dive into the research topics of 'Surface-assisted dehydrogenative homocoupling of porphine molecules'. Together they form a unique fingerprint.

Cite this