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Cooperative light-induced molecular movements of highly ordered azobenzene self-assembled monolayers.

ABSTRACT: Photochromic systems can convert light energy into mechanical energy, thus they can be used as building blocks for the fabrication of prototypes of molecular devices that are based on the photomechanical effect. Hitherto a controlled photochromic switch on surfaces has been achieved either on isolated chromophores or within assemblies of randomly arranged molecules. Here we show by scanning tunneling microscopy imaging the photochemical switching of a new terminally thiolated azobiphenyl rigid rod molecule. Interestingly, the switching of entire molecular 2D crystalline domains is observed, which is ruled by the interactions between nearest neighbors. This observation of azobenzene-based systems displaying collective switching might be of interest for applications in high-density data storage.

SUBMITTER: Pace G

PROVIDER: S-EPMC1891213 | biostudies-other | 2007 Jun

REPOSITORIES: biostudies-other

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Cooperative light-induced molecular movements of highly ordered azobenzene self-assembled monolayers.

Pace Giuseppina G Ferri Violetta V Grave Christian C Elbing Mark M von Hänisch Carsten C Zharnikov Michael M Mayor Marcel M Rampi Maria Anita MA Samorì Paolo P

Proceedings of the National Academy of Sciences of the United States of America 20070529 24

Photochromic systems can convert light energy into mechanical energy, thus they can be used as building blocks for the fabrication of prototypes of molecular devices that are based on the photomechanical effect. Hitherto a controlled photochromic switch on surfaces has been achieved either on isolated chromophores or within assemblies of randomly arranged molecules. Here we show by scanning tunneling microscopy imaging the photochemical switching of a new terminally thiolated azobiphenyl rigid r ...[more]

PMID: 17535889

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