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Mechanically induced single-molecule helicity switching of graphene-nanoribbon-fused helicene on Au(111).

ABSTRACT: Helicene is a functional material with chirality caused by its characteristic helical geometry. The inversion of its helicity by external stimuli is a challenging task in the advanced control of the molecular chirality. This study fabricated a novel helical molecule, specifically a pentahelicene-analogue twisted aromatic hydrocarbon fused with a graphene nanoribbon, via on-surface synthesis using multiple precursors. Noncontact atomic force microscopy imaging with high spatial resolution confirmed the helicity of the reaction products. The helicity was geometrically converted by pushing a CO-terminated tip into the twisted framework, which is the first demonstration of helicity switching at the single-molecule scale.

SUBMITTER: Ishii A

PROVIDER: S-EPMC8528025 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Mechanically induced single-molecule helicity switching of graphene-nanoribbon-fused helicene on Au(111).

Ishii Ayumu A Shiotari Akitoshi A Sugimoto Yoshiaki Y

Chemical science 20210914 40

Helicene is a functional material with chirality caused by its characteristic helical geometry. The inversion of its helicity by external stimuli is a challenging task in the advanced control of the molecular chirality. This study fabricated a novel helical molecule, specifically a pentahelicene-analogue twisted aromatic hydrocarbon fused with a graphene nanoribbon, <i>via</i> on-surface synthesis using multiple precursors. Noncontact atomic force microscopy imaging with high spatial resolution ...[more]

PMID: 34777748

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