Monomolecular Wheels

` Weird! This morning I checked out my inbox extra-early to find an article in the Materials Science and Nanotechnology section of Nature publications, describing an odd kind of rolling prototype vehicle that is 3x4 nanometers in size!

` Says the article:

Their chassis is shaped like a letter H, with two axles linked by a central rod. All these units are composed of carbon–carbon triple bonds alternating with benzene rings.

The key to the nanocar is the wheels. These are made of C₆₀ molecules attached to the tips of the axles, joined by bonds that are free to rotate.

` I am guessing that these molecules are cylinderical fullerenes, also called nanotubes.

These nanoscale molecules stick to a gold surface and, when warmed to above 170 °C, begin to move. This happens in a zigzag fashion: a nanocar travels in a single direction for a short distance, and then pivots to a new direction before proceeding again. The forward motion is always perpendicular to the orientation of the axles, which is evident from STM images in which the four C₆₀ molecules can be clearly seen.

` According to all the tests they've pulled on these things, the wheels really are rolling forward - in fact, ones with three different axles can only spin in place like office chairs with three fixed wheels.
` James Tour's team at the Rice University in Houston are the ones who are responsible for making what may be the smallest molecular monstrosities in Texas!