Towards controlled production of specific carbon nanostructures— a theoretical study on structural transformations of graphitic and diamond particles

Structural transformations of carbon nanoparticles are studied by means of molecular dynamics using a density-functional-based tight-binding method. The starting particles consist of 64 to 275 atoms arranged on a graphitic or diamond lattice. At elevated temperatures (1400 to 2800 K), the particles transform into spherical or elongated closed cages, concentric shell fullerenes, carbon nanotips, and spiraloidal and irregularly shaped clusters. The type of the final cluster depends essentially on the size and the atomic order of the starting particles, and on the temperature applied. The results show a way to proceed towards controlled preparation of specific carbon nanostructures.