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Evaluation of synthetic linear motor-molecule actuation energetics.

ABSTRACT: By applying atomic force microscope (AFM)-based force spectroscopy together with computational modeling in the form of molecular force-field simulations, we have determined quantitatively the actuation energetics of a synthetic motor-molecule. This multidisciplinary approach was performed on specifically designed, bistable, redox-controllable [2]rotaxanes to probe the steric and electrostatic interactions that dictate their mechanical switching at the single-molecule level. The fusion of experimental force spectroscopy and theoretical computational modeling has revealed that the repulsive electrostatic interaction, which is responsible for the molecular actuation, is as high as 65 kcal.mol(-1), a result that is supported by ab initio calculations.

SUBMITTER: Brough B

PROVIDER: S-EPMC1482623 | biostudies-literature | 2006 Jun

REPOSITORIES: biostudies-literature

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Evaluation of synthetic linear motor-molecule actuation energetics.

Brough Branden B Northrop Brian H BH Schmidt Jacob J JJ Tseng Hsian-Rong HR Houk Kendall N KN Stoddart J Fraser JF Ho Chih-Ming CM

Proceedings of the National Academy of Sciences of the United States of America 20060530 23

By applying atomic force microscope (AFM)-based force spectroscopy together with computational modeling in the form of molecular force-field simulations, we have determined quantitatively the actuation energetics of a synthetic motor-molecule. This multidisciplinary approach was performed on specifically designed, bistable, redox-controllable [2]rotaxanes to probe the steric and electrostatic interactions that dictate their mechanical switching at the single-molecule level. The fusion of experim ...[more]

PMID: 16735470

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