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Updated: Jun 2, 2026

Single Molecule Methods for Monitoring Changes in Bilayer Elastic Properties
Published on: November 3, 2008
Characteristics of amine-ended and thiol-ended alkane single-molecule junctions revealed by inelastic electron
Youngsang Kim1, Thomas Julian Hellmuth, Marius Bürkle
1Department of Physics, University of Konstanz, 78457 Konstanz, Germany.
Abstract:
A combined experimental and theoretical analysis of the charge transport through single-molecule junctions is performed to define the influence of molecular end groups for increasing electrode separation. For both amine-ended and thiol-ended octanes contacted to gold electrodes, we study signatures of chain formation by analyzing kinks in conductance traces, the junction length, and inelastic electron tunneling spectroscopy. The results show that for amine-ended molecular junctions no atomic chains are pulled under stretching, whereas the Au electrodes strongly deform for thiol-ended molecular junctions. This advanced approach hence provides unambiguous evidence that the amine anchors bind only weakly to Au.
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