Simultaneous Measurement of Force and Conductance Across Single Molecule Junctions

  • Sriharsha V. Aradhya
  • Michael Frei
  • Mark S. Hybertsen
  • Latha VenkataramanEmail author
Conference paper
Part of the Conference Proceedings of the Society for Experimental Mechanics Series book series (CPSEMS)


Measurement of electronics and mechanics of single molecules provides a fundamental understanding of conductance as well as bonding at the atomic scale. To study the mechanics at these length scales, we have built a conducting atomic force microscope (AFM) optimized for high displacement and force resolution. Here, we simultaneously measure conductance and force across single Au-molecule-Au junctions in order to obtain complementary information about the electronics and structure in these systems. First we show that single-atom Au contacts, which have a conductance of G0 (2e2/h), have a rupture force of about 1.4 nN, in excellent agreement with previous theoretical and experimental studies. For a series of amine and pyridine linked molecules which are bound to Au electrodes through an Au-N donor-acceptor bond, we observe that the rupture force depends on the backbone chemistry and can range from 0.5 to 0.8 nN. We also study junctions formed with molecules that bind through P-Au and S-Au interactions. We find that both the conductance signatures and junction evolution of covalent S-Au bond (thiolate) and a donor-acceptor S-Au bond (thiol) are dramatically different. Finally, we perform density functional theory based adiabatic molecular junction elongation and rupture calculations which give us an insight into the underlying mechanisms in these experiments.


Linker Group Force Event Breaking Force Molecular Junction Rupture Force 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was supported by the National Science Foundation (Career Award CHE-07-44185) and by the Packard Foundation. A portion of this work was performed using facilities in the Center for Functional Nanomaterials at Brookhaven National Laboratory and supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Contract No. DE-AC02-98CH10886.


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Copyright information

© The Society for Experimental Mechanics 2013

Authors and Affiliations

  • Sriharsha V. Aradhya
    • 1
  • Michael Frei
    • 1
  • Mark S. Hybertsen
    • 2
  • Latha Venkataraman
    • 1
    Email author
  1. 1.Department of Applied Physics and Applied MathematicsColumbia UniversityNew YorkUSA
  2. 2.Center for Functional NanomaterialsBrookhaven National LaboratoryUptonUSA

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