O(N) algorithms in tight-binding molecular-dynamics simulations of the electronic structure of carbon nanotubes

Abstract

A (formula presented) single-walled carbon nanotube consisting of 400 atoms with 20 layers is simulated under tensile loading using our developed (formula presented) parallel tight-binding molecular-dynamics algorithms. It is observed that the simulated carbon nanotube is able to carry the strain up to 122% of the relaxed tube length in elongation and up to 93% for compression. Young’s modulus, tensile strength, and the Poisson ratio are calculated and the values found are 0.311 TPa, 4.92 GPa, and 0.287, respectively. The stress-strain curve is obtained. The elastic limit is observed at a strain rate of 0.09 while the breaking point is at 0.23. The frequency of vibration for the pristine (formula presented) carbon nanotube in the radial direction is (formula presented) and it is sensitive to the strain rate.