▎ 摘　　要

We investigate the mechanical properties of graphene monolayer via the density functional theoretical (OFT) method. We find that the strain energies are anisotropic for the graphene under large strain. We attribute the anisotropic feature to the anisotropic sp(2) hybridization in the hexagonal lattice. We further identify that the formation energies of Stone-Wales (SW) defects in the graphene monolayer are determined by the defect concentration and also the direction of applied tensile strain, correlating with the anisotropic feature. (C) 2010 Elsevier B.V. All rights reserved.