Structural Transformations in Fullerite C60 under High-Pressure(P=12.5GPa) and High-Temperature Conditions.

Using quenching of samples to ambient conditions, we have studied structural transformations of fullerite C60 upon heating at P=12. 5 GPa, i. e., in the pressure range corresponding to the regime intermediate between collapses of fullerite C60 into the pure sp2 and sp3 amorphous carbon phases. A complicated picture of transformations, including the gradual crystal-to-amorphous transition with increase of the number of sp3 atomic sites (due to the 3D polymerization) and formation of graphitic clusters with the subsequent crystallization of diamond and graphite nanocrystals, was observed.