AUTOCATALYSIS DURING FULLERENE GROWTH

Total energy calculations with a local spin density functional have be en applied to the Stone-Wales transformation in fullerene (C-60). In t he formation of the almost exclusively observed I-h, isomer of C-60 wi th isolated pentagons, the final transformation must be from a C-2v is omer with two pentagon pairs. It was found that the energy barrier for this rearrangement was substantially reduced in the presence of an ex tra carbon atom. Such atoms were found to bind loosely, preferentially to regions in which there were paired pentagons. Pentagon rearrangeme nts, which are necessary steps in the growth of fullerenes, may theref ore result from autocatalysis by carbon.