Think the Smart car was too small to squeeze your fat ass into? You're in for a whole new world of pain, because the smallest working car has been built — and it's just one molecule in size.
A single-molecule car has been made before, but when its wheels turned, it didn't move. Useless.
But this little guy, called the nanocar, actually works. Developed by a team of Netherlands-based researchers, it's made up of a long central body with pivoted paddles at each of its four corners. The paddles can swing around in circles, and when a pulse of electrons is applied to them, they gain some energy and move... a whole quarter turn.
That quarter turn puts the molecule in to an unnatural arrangement, so the bonds continue to move another quarter turn to reach a state of equilibrium. To keep the car moving requires a pulse of electrons every half turn.
It sure ain't perfect. Especially when you find out that it takes 10 pulses of electrons to move the vehicle 6 nanometres. The head of a pin is about a million nanometres wide. Go figure.
Scientists have developed molecular motors in the past, but they spin on one of their axes so can never move themselves. Maybe combining the two will produce the molecular super car we're all hankering for. Or, y'know, at least one that can make it across the head of that pin. [Nature via New Scientist; Image: Scientific American]