Nonlinear elastic properties of graphene sheet using MM3 potential under finite deformation

MM3 interatomic potential is combined with Cauchy-Born rule for the first time to predict elastic properties of the graphene sheets at infinitesimal and finite strains. Further, using plane stress condition, basal plane stiffness and Poisson's ratio calculated using MM3 potential are found to be 310.59 nN/nm and 0.28, respectively. The elastic properties calculated using MM3 potential are somewhat better as compared to those of predicted through Tersoff-Brenner and second generation REBO potentials when compared with the experimental results. Elastic properties are also obtained with MM3 potential considering alternative empirical constants for bond stretch energy term. The present results are also compared with those obtained through modified Morse and first/second generation REBO potentials. The present multiscale model in the framework of MM3 potential will also facilitate the further investigations on the large atomistic structures with greater accuracy.