Special Reports

PRODUCING useful quantities of the football-shaped molecules known as buckyballs isn't easy if you want them bigger than the standard size. But now researchers have come up with a new trick: assemble them from zip-up flat-packs.

Buckyballs, or fullerenes, are usually made by blasting graphite with high-powered lasers. This clumsy process produces a soot of different-sized buckyballs. "You get C60 and C70 making up about 99 per cent, and tiny amounts of larger fullerenes like C76 and C78," says Lawrence Scott of Boston College in Chestnut Hill, Massachusetts. This makes it difficult to isolate useful amounts of the larger fullerenes scientists are keen to study.

Scott and his colleagues at the University of Warwick in Coventry think their way of making fullerenes will help. They took molecules made up of carbon rings and reacted them to produce flattened versions of buckyballs. To make C60, for example, they made a three-pronged molecule containing 60 carbon atoms. Zapping this molecule with laser light made the molecule curl up into a C60 buckyball. "You're really zipping the sides up," says Scott.

Because the size and shape of the flat molecules can be controlled, says Scott, they could be used to make large quantities of bigger buckyballs.