www.newscientist.com/news/news.jsp?id=ns99994942
Buckminsterfullerenes - buckyballs - are molecular spheres in which carbon atoms form interlinked pentagons and hexagons that resemble the panels on a soccer ball. Buckyballs, and the related carbon nanotubes, are extremely strong and very good conductors of electricity. This had led then to be common components of nanodevices such as tiny soldering irons and thermometers. But Su-Yuan Xie, from Xiamen University in south-east China, and colleagues made buckyballs from just 50 carbon atoms, by using a ring of 10 chlorine atoms as a belt to support the smaller structure. Other fullerenes with fewer than 60 carbon atoms have been created before, but none that so closely resembles the original buckyball. Isolated pentagons A remarkable feature of the new buckyballs is that they do not obey the "isolated pentagon rule". This mathematical law states that a structure will fall apart if the edges of two of its pentagon sides touch. The new molecules defy this thanks to the support of the chlorine atoms. Buckyballs and nanotubes are usually fabricated using an electric arc to vaporise carbon. They believe similar methods could be used to construct even smaller fullerene structures. Electronic properties More on this story 36 Subscribe to New Scientist for more news and features Related Stories 37 Soldering iron added to nano-toolkit 28 April 2004 38 Tiny 'elevator' most complex nanomachine yet 18 March 2004 39 Nanothermometer takes molecular temperatures 7 February 2002 For more related stories search the print edition 40 Archive Weblinks 41 Xiamen University 42 Fullerene Research Centre, Sussex University 43 Buckyballs, Stony Brook University Laszlo Mihaly, a buckyball researcher Stony Brook University in New York, US, says the molecules may turn out to have unusual conducting characteristics. This is because the carbon atoms should conduct electricity well, like a normal buckyball, but the chlorine ones should act as insulators. He says it will therefore be interesting to experiment with the structures.
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