Chiral Transition of the Supramolecular Assembly by Concentration Modulation at the Liquid/Solid Interface

Global hetero- and horriOchirai polymorphous assemblies from an achiral fluorenone derivative were successfully constructed With multiple intermolecular hydrogen bonds by concentration modulation. Scanning timneling microscopy investigations' reveal that a heterOdhikal supramolecular double rosette-like structure Was -fabricated for the -first time via hydrogen bond interactions with achiral 1-octanoic acid under low concentrations. When the solution concentration was increased-,:- the structural transition from a heterochiral, double rosettelike,structure-,,to a hoinochiral windmill-like pattern was ONerved. Interestingly, these two metastable structures ultimately coulcI-:transforin into a stable zigzag pattern at a bias voltage prompted by the STM tip, At high concentrations, only an achiral octamer arrangement could be Obtained, owing to thechanges of intermolecular hydrogen bonding, van der "W-,aals forcand dipole dipole interactions. The present- results provide& an importantfor the induction and control of polymorphcius chiral, structural transformation through modulated solution of achiral 1-octanoic acid.