One-Dimensional Lateral Force Anisotropy at the Atomic Scale in Sliding Single Molecules on a Surface

ORAL

Abstract

Using a q+ atomic force microscopy at low temperature, a sexiphenyl molecule is slid across an atomically flat Ag(111) surface along the direction parallel to its molecular axis and sideways to the axis. Despite identical contact area and underlying surface geometry, the lateral force required to move the molecule in the direction parallel to its molecular axis is found to be about half of that required to move it sideways. The origin of the lateral force anisotropy observed here is traced to the one-dimensional shape of the molecule, which is further confirmed by molecular dynamics simulations. We also demonstrate that scanning tunneling microscopy can be used to determine the comparative lateral force qualitatively. The observed one-dimensional lateral force anisotropy may have important implications in atomic scale frictional phenomena on materials surfaces.

*The STM experiments and analysis were supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Grant DE-FG02-02ER46012. Use of the Center for Nanoscale Materials, an Office of Science user facility, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02- 06CH11357. Y.L. is supported by the U.S. Department of Energy Office of Basic Energy Sciences (SISGR Grant DE-FG02-09ER16109). L.A.C. and A.T.N. were supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Materials Science and Engineering.

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Publication: Y. Zhang, D.J. Trainer, B. Narayanan, Y. Li, A.T. Ngo, S. Khadka, A. Neogi, B. Fisher, L.A. Curtiss, S.K.R.S. Sankaranarayanan, S.W. Hla. One-Dimensional Lateral Force Anisotropy at the Atomic Scale in Sliding Single Molecules on a Surface. Nano Letters 21, 6391-6397 (2021).

Presenters

  • Yuan Zhang

    • Department of Physics, Old Dominion University, Norfolk, Virginia 23529, United States
    • Old Dominion University

Authors

  • Yuan Zhang

    • Department of Physics, Old Dominion University, Norfolk, Virginia 23529, United States
    • Old Dominion University

  • Daniel J Trainer

    • Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
    • Argonne National Laboratory
    • Temple University

  • Badri Narayanan

    • University of Louisville

  • Yang Li

    • ohio university

  • Anh T Ngo

    • Univ of Illinois at Chicago & MSD, ANL
    • University of Illinois at Chicago
    • Univeristy of Illinois at Chicago; Argonne National Laboratory
    • Argonne National Laboratory
    • Chemical Engineering Department, University of Illinois at Chicago

  • Sushila Khadka

    • Ohio University

  • Arnab Neogi

    • Argonne National Laboratory

  • Brandon Fisher

    • Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
    • Argonne National Laboratory

  • Larry A Curtiss

    • Materials Science Division, Argonne National Laboratory, Argonne, IL, USA, Joint Center for Energy Storage Research (JCESR), Argonne, IL, USA.
    • MSD, ANL
    • Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory

  • Subramanian Sankaranarayanan

    • University of Illinois, Argonne National Lab
    • University of Illinois, Argonne National
    • University of Illinois, Argonne National Laboratory

  • Saw Wai, Hla

    • Argonne National Lab; Ohio University
    • Argonne National Laboratory
    • Argonne National Laboratory; Ohio University