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Observation of Collective Photoswitching in Free-Standing TATA-Based Azobenzenes on Au(111).

ABSTRACT: Light-induced transitions between the trans and cis isomer of triazatriangulenium-based azobenzene derivatives on Au(111) surfaces were observed directly by scanning tunneling microscopy, allowing atomic-scale studies of the photoisomerization kinetics. Although the azobenzene units in these adlayers are free-standing and spaced at uniform distances of 1.26?nm, their photoswitching depends on the isomeric state of the surrounding molecules and, specifically, is accelerated by neighboring cis isomers. These collective effects are supported by ab?initio calculations indicating that the electronic excitation preferably localizes on the n-?* state of trans isomers with neighboring cis azobenzenes.

SUBMITTER: Rusch TR

PROVIDER: S-EPMC7540444 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Observation of Collective Photoswitching in Free-Standing TATA-Based Azobenzenes on Au(111).

Rusch Talina R TR Schlimm Alexander A Krekiehn Nicolai R NR Tellkamp Tobias T Budzák Šimon Š Jacquemin Denis D Tuczek Felix F Herges Rainer R Magnussen Olaf M OM

Angewandte Chemie (International ed. in English) 20200727 39

Light-induced transitions between the trans and cis isomer of triazatriangulenium-based azobenzene derivatives on Au(111) surfaces were observed directly by scanning tunneling microscopy, allowing atomic-scale studies of the photoisomerization kinetics. Although the azobenzene units in these adlayers are free-standing and spaced at uniform distances of 1.26 nm, their photoswitching depends on the isomeric state of the surrounding molecules and, specifically, is accelerated by neighboring cis iso ...[more]

PMID: 32524693

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