In the first demonstration of an electrically driven molecular motor, an electric current spins a single molecule like a pinwheel.

Charles Sykes and his colleagues at Tufts University in Medford, Massachusetts, used a scanning tunnelling microscope to capture images of the molecule, butyl methyl sulphide, as it spun on a copper surface (pictured). The microscope also supplied the current to power the motion.

The molecule had a small preference for clockwise rotation in one experimental set-up. This shows that it could be used as a motor, rather than just a rotor, in molecular machines, the researchers say.

Nature Nanotechnol. 10.1038/NNANO.2011.142 (2011)