GeV latent ion tracks in sugar; fullerenes and other radiochemical products

Abstract It is now known that fullerenes, large atomic carbon clusters, and polycyclic compounds, remain in the latent tracks of sufficiently energetic ions in carbonaceous condensed matter. For the polycyclic compound production a characteristic threshold of a few eV A 3 in transferred electronic energy must be exceeded. For more general and especially more quantitative purposes, sugar was selected as the ion beam target for the experiments described. Sugar is readily dissolved, and radiochemical products along the ion track are accessible for quantitative assessement. We report an observation of the genesis of the singular fullerenes C 60 and C 70 in ion tracks, and we present a simple theoretical model for fullerene growth from a primeval soup. Specifically, we found in 3 GeV U 20+ ion tracks the production of 53 to 114 C 60 molecules, and about 3 C 70 molecules per track. Additionally a variety of other radiochemical products emerges, which are characterized by e.g. CC double bonds, cyclic rings and even pentagons. For contrast, CH 2 − and CH 3 − groups, normally very pronounced in sugar, vanish. Finally, there are indications for the emergence of either carbon cluster or polymer formation.