Three-dimensional modal analysis of carbon nanocones using molecular dynamics simulation

The resonant frequencies of carbon nanocones and their corresponding mode shapes are investigated through molecular dynamics simulations. The three-dimensional vibrational mode shapes are extracted using the time histories of the three coordinates of each atom obtained from conducting one molecular dynamics simulation. Unlike the previous studies, the proposed technique is able to predict precisely all of the possible mode shapes including transverse, radial, torsional, and longitudinal modes within one molecular dynamics run. The effects of length, apex angle, and boundary conditions on the resonant characteristics of carbon nanocones are examined. The results indicate that the apex angle not only affects the resonant frequencies but also influences the shape and order of modal displacements. In addition, it is observed that the sensitivity of the resonant frequencies to the boundary conditions depends on the shape of the modal displacement.