Fracture-induced Stone-Wales defect generation in carbon nanotube

Abstract

Quantum-chemical modeling of (8, 0) carbon nanotube (CNT) structure within the framework of INDO parametrization (same as that used for other condensed carbon phases) revealed specific features of the formation of a Stone-Wales (SW) defect representing 5-7-7-5 topochemical rotation of one bond in the graphene lattice. The rolling-up of a planar carbon lattice of graphene into a nanotube leads to an approximately 0.6 eV decrease in the energy of defect formation. The SW defect introduces resonant, rather than discrete, energy levels into the electron spectrum of the CNT. In the case of a fractured CNT, the SW defect formation energy is smaller in the region of compression. At a fracture angle above the critical value (1.7°), the appearance of a defect decreases the CNT energy. The fracturing strain leads to the mechanical plastic generation of SW defects.