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Rotational and constitutional dynamics of caged supramolecules.

ABSTRACT: The confinement of molecular species in nanoscale environments leads to intriguing dynamic phenomena. Notably, the organization and rotational motions of individual molecules were controlled by carefully designed, fully supramolecular host architectures. Here we use an open 2D coordination network on a smooth metal surface to steer the self-assembly of discrete trimeric guest units, identified as noncovalently bound dynamers. Each caged chiral supramolecule performs concerted, chirality-preserving rotary motions within the template honeycomb pore, which are visualized and quantitatively analyzed using temperature-controlled scanning tunneling microscopy. Furthermore, with higher thermal energies, a constitutional system dynamics appears, which is revealed by monitoring repetitive switching events of the confined supramolecules' chirality signature, reflecting decay and reassembly of the caged units.

SUBMITTER: Kuhne D

PROVIDER: S-EPMC3003120 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

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Rotational and constitutional dynamics of caged supramolecules.

Kühne Dirk D Klappenberger Florian F Krenner Wolfgang W Klyatskaya Svetlana S Ruben Mario M Barth Johannes V JV

Proceedings of the National Academy of Sciences of the United States of America 20101122 50

The confinement of molecular species in nanoscale environments leads to intriguing dynamic phenomena. Notably, the organization and rotational motions of individual molecules were controlled by carefully designed, fully supramolecular host architectures. Here we use an open 2D coordination network on a smooth metal surface to steer the self-assembly of discrete trimeric guest units, identified as noncovalently bound dynamers. Each caged chiral supramolecule performs concerted, chirality-preservi ...[more]

PMID: 21098303

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