European nanotechnology team builds molecular rack-and-pinion

Christian Joachim, winner of Feynman Prizes in Nanotechnology for both experiment and theory, continues his exciting molecular machine systems work with a recent publication authored by a German/French team in Nature Materials titled “A rack-and-pinion device at the molecular scale“. From the summary and conclusion:

In this work, we present a molecular rack-and-pinion device for which an STM tip drives a single pinion molecule at low temperature. The pinion is a 1.8-nm-diameter molecule functioning as a six-toothed wheel interlocked at the edge of a self-assembled molecular island acting as a rack. We monitor the rotation of the pinion molecule tooth by tooth along the rack by a chemical tag attached to one of its cogs…

In conclusion, we have observed a molecular ‘rack-and-pinion’ mechanism at work with an atomic-scale precision. We obtained this by a full sequence of steps comprising the careful design and synthesis of the molecule, the surface preparation and the assembly of the molecular pinion on its molecular rack. Combined with the atomic-scale understanding of the physics of its movement, the piece-by-piece assembly of such a device opens a new way of exploring the functioning of a molecular machine.

The work was funded by the Volkswagen Foundation Project ‘Single molecule synthesis’ and the European Projects NANOMAN and AMMIST. For the Volkswagen Foundation Project, see the last grant on this page. So: if you’ve ever purchased a Volkswagen, you may have helped support this work!

Although Nature Materials, like the other Nature journals, is very good, I can’t help but wish that nanotech work like this would instead be published in a PLoS journal, so we could all see the full text. PLoS currently focuses on biology and medicine, but we can hope they will expand.

Also, is it just me, or are we seeing more visionary experimental work on artificial molecular machine systems in Europe than in the U.S.? No wonder the September 2006 National Academies report on the U.S. NNI called for improved coordination in this area. —Christine