Molecular dynamics in formation process of SWNTs

The formation mechanism of single-walled carbon nanotubes (SWNTs) was studied with the molecular dynamics simulation. Starting from randomly distributed carbon and Ni atoms, random cage structures of carbon atoms with a few Ni atoms were obtained after 6 ns simulation. Ni atoms on the random cage prohibited the complete closure and anneal of the cage structure into the fullerene structure. In the next stage the simulation cell size was artificially shrunk for realization of proceeding collisions of precursor clusters within the computational time limit. Collisions of such imperfect random-cage clusters lead to an elongated tubular cage structure, which can be regarded as an imperfect SWNT.