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Unbalanced 2D Chiral Crystallization of Pentahelicene Propellers and Their Planarization into Nanographenes.

ABSTRACT: The chiral self-assembly of trispentahelicene propellers on a gold surface has been investigated in ultrahigh vacuum by means of scanning tunneling microscopy and time-of-flight secondary ion mass spectrometry. The trispentahelicene propellers aggregate into mirror domains with an enantiomeric ratio of 2 : 1. Thermally induced cyclodehydrogenation leads to planarization into nanographenes, which self-assemble into closed-packed layers with two different azimuths. Further treatment induces in part dimerization and trimerization by intermolecular cyclodehydrogenation.

SUBMITTER: Voigt J

PROVIDER: S-EPMC8362048 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Unbalanced 2D Chiral Crystallization of Pentahelicene Propellers and Their Planarization into Nanographenes.

Voigt Jan J Roy Myriam M Baljozović Miloš M Wäckerlin Christian C Coquerel Yoann Y Gingras Marc M Ernst Karl-Heinz KH

Chemistry (Weinheim an der Bergstrasse, Germany) 20210608 40

The chiral self-assembly of trispentahelicene propellers on a gold surface has been investigated in ultrahigh vacuum by means of scanning tunneling microscopy and time-of-flight secondary ion mass spectrometry. The trispentahelicene propellers aggregate into mirror domains with an enantiomeric ratio of 2 : 1. Thermally induced cyclodehydrogenation leads to planarization into nanographenes, which self-assemble into closed-packed layers with two different azimuths. Further treatment induces in par ...[more]

PMID: 34042228

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