GROWTH OF CARBON NANOTUBES - A MOLECULAR-DYNAMICS STUDY

Molecular dynamics with realistic many-body atomic potentials was used to study the growth of carbon nanotubes. Analysis of the bond switchi ng and ring migration processes has led to an identification of tube g rowth mechanisms. Wide tubes, initially open, were found to grow strai ght maintaining an all-hexagonal structure, while narrow tubes were fo und to develop permanent pentagonal rings that lead to tube closure up on further deposition. Continued deposition on the top of a closed tub e yields a disordered cap structure, implying that open tubes are crit ical for defect-free growth.