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Experiments with irradiated single-walled carbon nanotubes are shown to generate a set of probability distribution functions and to derive a set of information theoretic entropy-based parameters. Energetic Cs + ions initiate linear collision cascades and nonlinear thermal spikes in single-walled carbon nanotubes. The probability distribution functions are constructed from the normalized experimental yields of the sputtered atoms and clusters. The information or Shannon entropy and fractal dimension are evaluated for each of the emitted species. Along with the fractal dimension, the information is used to identify and distinguish the energy dissipation processes that generate conditions for monatomic sputtering and clusters emissions.

A model has been developed that illustrates C 60 's emergence from the condensing carbon vapour.It is shown to depend upon (i) the decreasing heats of formation for larger cages, (ii) exponentially increasing number of isomers for fullerenes that are larger than C 60 , (iii) large cages' buckling induced by the pentagon-related protrusions that initiate fragmentation, (iv) the structural instability-induced fragmentation that shrinks large cages via an evolving gas of C 2 that is crucial to the whole process. The model describes a mechanism for the provision and presence of plenty of C 2 s during the formation and fragmentation processes.Fullerenes portrayed as 3D rotors have partition functions describing ensemble's entropy as a function of the fragmentation sequence. The bottom-up formations of large cages followed by the top-down cage shrinkage are shown to be stable, dynamical processes that lead to the C 60 dominated fullerene ensemble.