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Correlation of breaking forces, conductances and geometries of molecular junctions.

ABSTRACT: Electrical and mechanical properties of elongated gold-molecule-gold junctions formed by tolane-type molecules with different anchoring groups (pyridyl, thiol, amine, nitrile and dihydrobenzothiophene) were studied in current-sensing force spectroscopy experiments and density functional simulations. Correlations between forces, conductances and junction geometries demonstrate that aromatic tolanes bind between electrodes as single molecules or as weakly-conductive dimers held by mechanically-weak ? - ? stacking. In contrast with the other anchors that form only S-Au or N-Au bonds, the pyridyl ring also forms a highly-conductive cofacial link to the gold surface. Binding of multiple molecules creates junctions with higher conductances and mechanical strengths than the single-molecule ones.

SUBMITTER: Yoshida K

PROVIDER: S-EPMC4355744 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Correlation of breaking forces, conductances and geometries of molecular junctions.

Yoshida Koji K Pobelov Ilya V IV Manrique David Zsolt DZ Pope Thomas T Mészáros Gábor G Gulcur Murat M Bryce Martin R MR Lambert Colin J CJ Wandlowski Thomas T

Scientific reports 20150311

Electrical and mechanical properties of elongated gold-molecule-gold junctions formed by tolane-type molecules with different anchoring groups (pyridyl, thiol, amine, nitrile and dihydrobenzothiophene) were studied in current-sensing force spectroscopy experiments and density functional simulations. Correlations between forces, conductances and junction geometries demonstrate that aromatic tolanes bind between electrodes as single molecules or as weakly-conductive dimers held by mechanically-wea ...[more]

PMID: 25758349

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