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Electrically driven directional motion of a four-wheeled molecule on a metal surface


Propelling single molecules in a controlled manner along an unmodified surface remains extremely challenging because it requires molecules that can use light, chemical or electrical energy to modulate their interaction with the surface in a way that generates motion. Nature’s motor proteins1,2 have mastered the art of converting conformational changes into directed motion, and have inspired the design of artificial systems3 such as DNA walkers4,5 and light- and redox-driven molecular motors6,7,8,9,10,11. But although controlled movement of single molecules along a surface has been reported12,13,14,15,16, the molecules in these examples act as passive elements that either diffuse along a preferential direction with equal probability for forward and backward movement or are dragged by an STM tip. Here we present a molecule with four functional units—our previously reported rotary motors6,8,17—that undergo continuous and defined conformational changes upon sequential electronic and vibrational excitation. Scanning tunnelling microscopy confirms that activation of the conformational changes of the rotors through inelastic electron tunnelling propels the molecule unidirectionally across a Cu(111) surface. The system can be adapted to follow either linear or random surface trajectories or to remain stationary, by tuning the chirality of the individual motor units. Our design provides a starting point for the exploration of more sophisticated molecular mechanical systems with directionally controlled motion.

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Figure 1: Structure of the four-wheeled molecule.
Figure 2: Linear movement of the meso-(R,S-R,S ) isomer.
Figure 3: Helix inversion at lower bias voltage and polarity dependence of propulsion.
Figure 4: Control over motion by the geometries of the four motors.


  1. Schliwa, M. & Woehlke, G. Molecular motors. Nature 422, 759–765 (2003)

    Article  CAS  ADS  Google Scholar 

  2. van den Heuvel, M. G. L. & Dekker, C. Motor proteins at work for nanotechnology. Science 317, 333–336 (2007)

    Article  CAS  ADS  Google Scholar 

  3. Ismagilov, R. F., Schwartz, A., Bowden, N. & Whitesides, G. M. Autonomous movement and self-assembly. Angew. Chem. Int. Edn Engl. 41, 652–654 (2002)

    Article  CAS  Google Scholar 

  4. Lund, K. et al. Molecular robots guided by prescriptive landscapes. Nature 465, 206–210 (2010)

    Article  CAS  ADS  Google Scholar 

  5. Gu, H., Chao, J., Xiao, S.-J. & Seeman, N. C. A proximity-based programmable DNA nanoscale assembly line. Nature 465, 202–205 (2010)

    Article  CAS  ADS  Google Scholar 

  6. Browne, W. R. & Feringa, B. L. Making molecular machines work. Nature Nanotechnol. 1, 25–35 (2006)

    Article  CAS  ADS  Google Scholar 

  7. Kay, E. R., Leigh, D. A. & Zerbetto, F. Synthetic molecular motors and mechanical machines. Angew. Chem. Int. Edn Engl. 46, 72–191 (2007)

    Article  CAS  Google Scholar 

  8. Koumura, N., Zijlstra, R. W. J., van Delden, R. A., Harada, N. & Feringa, B. L. Light-driven molecular rotor. Nature 401, 152–155 (1999)

    Article  CAS  ADS  Google Scholar 

  9. Balzani, V., Credi, A., Raymo, F. M. & Stoddart, J. F. Artificial molecular machines. Angew. Chem. Int. Edn Engl. 39, 3348–3391 (2000)

    Article  CAS  Google Scholar 

  10. van Delden, R. A. et al. Unidirectional molecular motor on a gold surface. Nature 437, 1337–1340 (2005)

    Article  CAS  ADS  Google Scholar 

  11. Green, J. E. et al. A 160-kilobit molecular electronic memory patterned at 1011 bits per square centimeter. Nature 445, 414–417 (2007)

    Article  CAS  ADS  Google Scholar 

  12. Shirai, Y., Osgood, A. J., Zhao, Y., Kelly, K. F. & Tour, J. M. Directional control in thermally driven single-molecule nanocars. Nano Lett. 5, 2330–2334 (2005)

    Article  CAS  ADS  Google Scholar 

  13. Wong, K. L. et al. A molecule carrier. Science 315, 1391–1393 (2007)

    Article  CAS  ADS  Google Scholar 

  14. Gimzewski, J. K. & Joachim, C. Nanoscale science of single molecules using local probes. Science 283, 1683–1688 (1999)

    Article  CAS  ADS  Google Scholar 

  15. Grill, L. et al. Rolling a single molecular wheel at the atomic scale. Nature Nanotechnol. 2, 95–98 (2007)

    Article  CAS  ADS  Google Scholar 

  16. Chiaravalloti, F. et al. A rack-and-pinion device at the molecular scale. Nature Mater. 6, 30–33 (2007)

    Article  CAS  ADS  Google Scholar 

  17. Eelkema, R. et al. Nanomotor rotates microscale objects. Nature 440, 163 (2006)

    Article  CAS  ADS  Google Scholar 

  18. Iancu, V., Deshpande, A. & Hla, S.-W. Manipulating Kondo temperature via single molecule switching. Nano Lett. 6, 820–823 (2006)

    Article  CAS  ADS  Google Scholar 

  19. Qiu, X. H., Nazin, G. V. & Ho, W. Mechanisms of reversible conformational transitions in a single molecule. Phys. Rev. Lett. 93, 196806 (2004)

    Article  CAS  ADS  Google Scholar 

  20. Lastapis, M. et al. Picometer-scale electronic control of molecular dynamics inside a single molecule. Science 308, 1000–1003 (2005)

    Article  CAS  ADS  Google Scholar 

  21. Alemani, M. et al. Adsorption and switching properties of azobenzene derivatives on different noble metal surfaces: Au(111), Cu(111), and Au(100). J. Phys. Chem. C 112, 10509–10514 (2008)

    Article  CAS  Google Scholar 

  22. Sainoo, Y., Kim, Y., Komeda, T., Kawai, M. & Shigekawa, H. Observation of cis-2-butene molecule on Pd(110) by cryogenic STM: site determination using tunneling-current-induced rotation. Surf. Sci. 536, L403–L407 (2003)

    Article  CAS  ADS  Google Scholar 

  23. Henzl, J. & Morgenstern, K. An electron induced two-dimensional switch made of azobenzene derivatives anchored in supramolecular assemblies. Phys. Chem. Chem. Phys. 12, 6035–6044 (2010)

    Article  CAS  Google Scholar 

  24. Lukas, S., Vollmer, S., Witte, G. & Wöll, C. Adsorption of acenes on flat and vicinal Cu(111) surfaces: step induced formation of lateral order. J. Chem. Phys. 114, 10123–10130 (2001)

    Article  CAS  ADS  Google Scholar 

  25. Ueba, H. & Persson, B. N. Action spectroscopy for single-molecule motion induced by vibrational excitation with a scanning tunneling microscope. Phys. Rev. B 75, 041403 (2007)

    Article  ADS  Google Scholar 

  26. Parschau, M., Passerone, D., Rieder, K.-H., Hug, H. J. & Ernst, K.-H. Switching the chirality of a single adsorbate. Angew. Chem. Int. Edn Engl. 48, 4065–4068 (2009)

    Article  CAS  Google Scholar 

  27. Seideman, T. Current-driven dynamics in molecular-scale devices. J. Phys. Condens. Matter 15, R521,–doi:10.1088/0953-8984/15/14/201 (2003)

    Article  CAS  ADS  Google Scholar 

  28. Eigler, D. M., Lutz, C. P. & Rudge, W. E. An atomic switch realized with the scanning tunnelling microscope. Nature 352, 600–603 (1991)

    Article  CAS  ADS  Google Scholar 

  29. Parschau, M., Rieder, K.-H., Hug, H. J. & Ernst, K.-H. Single-molecule chemistry and analysis: mode-specific dehydrogenation of adsorbed propene by inelastic electron tunneling. J. Am. Chem. Soc. 133, 5689–5691 (2011)

    Article  CAS  Google Scholar 

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This research was supported by the Netherlands Organization for Scientific Research (NWO-CW) (B.L.F. and T.K. through a VENI grant), the Swiss Secretary for Education and Research and the Swiss National Science Foundation (K.-H.E. and M.P.), and the European Research Council (ERC advanced grant 227897 to B.L.F.).

Author information

Authors and Affiliations



N.R., B.M., S.R.H. and B.L.F. designed the four-wheeled molecule and N.R. conducted its synthesis and characterization. T.K., M.P., N.K. and K.-H.E. designed the STM experiments and contributed to their interpretation. T.K. and M.P. performed the STM experiments at Empa. T.K., K.-H.E. and B.L.F. wrote the manuscript. S.R.H., K.-H.E. and B.L.F. conceived and guided the research. All authors discussed the results and implications and commented on the manuscript at all stages.

Corresponding authors

Correspondence to Syuzanna R. Harutyunyan, Karl-Heinz Ernst or Ben L. Feringa.

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Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

This file contains Supplementary Information comprising Supplementary Sections 1-5 (see Contents), which include a Supplementary Discussion, Supplementary Text and Data, Supplementary Figures 1-10 with legends and full legends for Supplementary Movies 1-4. (PDF 2725 kb)

Supplementary Movie 1

In this movie we see preferentially linear movement of the meso-isomer of the four-wheeled molecule after excitation - see Supplementary Information for full legend. (MOV 185 kb)

Supplementary Movie 2

In this movie we see changes in STM contrast induced by helix inversion of the motor units of the four-wheeled molecule after vibrational excitation - see Supplementary Information for full legend. (MOV 162 kb)

Supplementary Movie 3

In this movie we see the random movement of one enantiomer of the racemic version of the four-wheeled molecule after excitation - see Supplementary Information for full legend. (MOV 850 kb)

Supplementary Movie 4

In this movie we see a molecular model for the anticipated linear propulsion of the meso-form of the four-wheeled molecule - see Supplementary Information for full legend. (MOV 800 kb)

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Kudernac, T., Ruangsupapichat, N., Parschau, M. et al. Electrically driven directional motion of a four-wheeled molecule on a metal surface. Nature 479, 208–211 (2011).

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