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Mechanically induced single-molecule helicity switching of graphene-nanoribbon-fused helicene on Au(111)† † Electronic supplementary information (ESI) available: Experimental method, optimisation of the synthesis procedure for helical products, sequential switching, verification of switching ability with different conditions, and estimation of the activation barrier for the helicity inversion. See DOI: 10.1039/d1sc03976h

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. Graphene nanoribbon-fused helicene was fabricated via on-surface synthesis. The helicity of the product was reversibly switchable by pushing a CO-terminated scanning-probe-microscopy tip into the protruding helical terminal.

SUBMITTER: Ishii A

PROVIDER: S-EPMC8528025 | biostudies-literature |

REPOSITORIES: biostudies-literature

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