TOPOLOGICAL DEFECTS IN LARGE FULLERENES

A topological defect consisting of a five- and a seven-membered ring pair in a honeycomb lattice is proposed. The defect pair can move smoothly in a honeycomb lattice during a bond change reaction without annihilation into two six-membered rings, until the defect pair collides with another pentagon defect. The relationship between the stability and the alignment of pentagons in a general fullerene, and a mechanism for the crystal growth of chiral graphene tubules are discussed using the idea of this topological defect.