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Self-organization of nano-lines and dots triggered by a local mechanical stimulus.

ABSTRACT: When a local mechanical perturbation is applied to the surface of a thin film of a mechanically interlocked molecule (a rotaxane), the molecules self-organize into periodic arrays of discrete dots or lines. The dimensionality of the nanostructures depends on whether the mechanical stimulus acts along a 1D line or over a 2D area. The size (50-500 nm) and periodicity (100-600 nm) of the patterns are controlled solely by the film thickness. This self-organization at the mesoscopic scale occurs via a nucleation-ripening mechanism eased by the relatively low energy barriers of the intramolecular rearrangement introduced by the mechanical bond. The phenomenon can be exploited as a bottom-up nanofabrication method.

SUBMITTER: Biscarini F

PROVIDER: S-EPMC1693801 | biostudies-literature | 2006 Nov

REPOSITORIES: biostudies-literature

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Self-organization of nano-lines and dots triggered by a local mechanical stimulus.

Biscarini Fabio F Cavallini Massimiliano M Kshirsagar Rajendra R Bottari Giovanni G Leigh David A DA León Salvador S Zerbetto Francesco F

Proceedings of the National Academy of Sciences of the United States of America 20061107 47

When a local mechanical perturbation is applied to the surface of a thin film of a mechanically interlocked molecule (a rotaxane), the molecules self-organize into periodic arrays of discrete dots or lines. The dimensionality of the nanostructures depends on whether the mechanical stimulus acts along a 1D line or over a 2D area. The size (50-500 nm) and periodicity (100-600 nm) of the patterns are controlled solely by the film thickness. This self-organization at the mesoscopic scale occurs via ...[more]

PMID: 17090680

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