Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Step-by-step rotation of a molecule-gear mounted on an atomic-scale axis


Gears are microfabricated down to diameters of a few micrometres. Natural macromolecular motors, of tens of nanometres in diameter, also show gear effects1. At a smaller scale, the random rotation of a single-molecule rotor encaged in a molecular stator has been observed2, demonstrating that a single molecule can be rotated with the tip of a scanning tunnelling microscope3,4 (STM). A self-assembled rack-and-pinion molecular machine where the STM tip apex is the rotation axis of the pinion was also tested5. Here, we present the mechanics of an intentionally constructed molecule-gear on a Au(111) surface, mounting and centring one hexa-t-butyl-pyrimidopentaphenylbenzene molecule on one atom axis. The combination of molecular design, molecular manipulation and surface atomic structure selection leads to the construction of a fundamental component of a planar single-molecule mechanical machine. The rotation of our molecule-gear is step-by-step and totally under control, demonstrating nine stable stations in both directions.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type



Prices may be subject to local taxes which are calculated during checkout

Figure 1: HB-NBP molecule.
Figure 2: Surface repulsive barrier, HB-NBP versus herringbone ridge.
Figure 3: Molecule-gear construction.
Figure 4: Molecule-gear rotation.


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

    CAS  Google Scholar 

  2. Gimzewski, J. K. et al. Rotation of a single molecule within a supramolecular bearing. Science 281, 531–533 (1998).

    Article  CAS  Google Scholar 

  3. Stipe, B. C., Rezaei, M. A. & Ho, W. Inducing and viewing the rotational motion of a single molecule. Science 279, 1907–1909 (1998).

    Article  CAS  Google Scholar 

  4. Stipe, B. C., Rezaei, M. A. & Ho, W. Coupling of vibrational excitation to the rotational motion of a single adsorbed molecule. Phys. Rev. Lett. 81, 1263–1266 (1998).

    Article  CAS  Google Scholar 

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

    Article  Google Scholar 

  6. Gross, L. et al. Tailoring molecular self-organization by chemical synthesis: Hexaphenylbenzene, hexa-peri-hexabenzocoronene, and derivatives on Cu (111). Phys. Rev. B 71, 165428 (2005).

    Article  Google Scholar 

  7. De Sarkar, A., Manzano, C., Soe, W.-H., Chandrasekhar, N. & Joachim, C. Conformational dependence of tag induced intramolecular STM contrast in hexaphenylbenzene molecules. Surf. Sci. Lett. 603, L57–L61 (2009).

    Article  CAS  Google Scholar 

  8. Barth, J. V., Brune, H., Ertl, G. & Behm, R. J. Scanning tunneling microscopy observations on the reconstructed Au(111) surface: Atomic structure, long-range superstructure, rotational domains, and surface defects. Phys. Rev. B 42, 9307–9318 (1990).

    Article  CAS  Google Scholar 

  9. Eigler, D. M. & Schweizer, E. K. Positioning single atoms with a scanning tunneling microscope. Nature 344, 524–526 (1990).

    Article  CAS  Google Scholar 

  10. Stroscio, J. A. & Eigler, D. M. Atomic and molecular manipulation with the scanning tunneling microscope. Science 254, 1319–1326 (1991).

    Article  CAS  Google Scholar 

  11. Jung, T. A., Schlittler, R. R., Gimzewski, J. K., Tang, H. & Joachim, C. Controlled room-temperature positioning of individual molecules: Molecular flexure and motion. Science 271, 181–184 (1996).

    Article  CAS  Google Scholar 

  12. Meyer, G. & Rieder, K.-H. Controlled manipulation of single atoms and small molecules with the scanning tunneling microscope. Surf. Sci. 377–379, 1087–1093 (1997).

    Article  Google Scholar 

  13. Gross, L. et al. Trapping and moving metal atoms with a six-leg molecule. Nature Mater. 4, 892–895 (2005).

    Article  CAS  Google Scholar 

  14. Ample, F. & Joachim, C. A semi-empirical study of polyacene molecules adsorbed on a Cu(110) surface. Surf. Sci. 600, 3243–3251 (2006).

    Article  CAS  Google Scholar 

  15. Sautet, P. & Joachim, C. Calculation of the benzene on rhodium STM images. Chem. Phys. Lett. 185, 23–30 (1991).

    Article  CAS  Google Scholar 

Download references


We acknowledge the Agency for Science Technology and Research (A*STAR) for financial support provided through the Visiting Investigatorship Program (phase I) ‘Atomic Scale Technology Project’.

Author information

Authors and Affiliations



C.M. and W.-H.S. were equally responsible for conducting the whole STM experiments, H.S.W. provided support with the experiments, A.G. and C.J. were responsible for the molecular design, A.G. for the chemical synthesis, F.A. and C.J. for the calculations, and N.C. and C.J. were responsible for the interpretation and planning of the experiments.

Corresponding authors

Correspondence to C. Manzano or W.-H. Soe.

Supplementary information

Supplementary Information

Supplementary Information (PDF 421 kb)

Supplementary Information

Supplementary Movie 1 (AVI 1461 kb)

Supplementary Information

Supplementary Movie 2 (AVI 2072 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Manzano, C., Soe, WH., Wong, H. et al. Step-by-step rotation of a molecule-gear mounted on an atomic-scale axis. Nature Mater 8, 576–579 (2009).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing