Molecular dynamics investigation of carbon nanotube resonance

In this work, a methodology to directly extract resonant information from an equilibrium molecular dynamics simulation is proposed and demonstrated by analyzing the vibrational behavior of carbon nanotubes (CNTs). Different vibrational motions, i.e. longitudinal, transverse, rotational and radial, could be easily distinguished and computed through the time sequence of the velocity components of atoms at the equilibrating process. Fast Fourier transform is adopted to perform the transformation of vibration information from time to frequency domain. The effects of CNT length, radius and boundary condition on the resonant behaviors of CNTs are systematically investigated. Moreover, the simulation results are compared with those predicted based on the Euler-Bernoulli beam theory. Note that the simulated longitudinal and rotational resonant behaviors agree quite well with the theoretical prediction and a slight deviation is observed in the transverse prediction.