Mechanics of C60 in Armchair Nanotubes

The large empty spaces inside carbon nanotubes are large enough to accommodate one or more fullerene inside. These structures could have different physical properties compared to empty nanotubes. The discoveries of these carbon nanopeapods have opened opportunities for different applications of carbon nanostructures [1].Berber et al [2] showed that the Fullerene encapsulation process does not involve an activation energy barrier, and Qian et al [3] showed that C60 is sucked into the (10, 10) CNT by the sharp surface tension force presented at the front of the open end and then oscillated between the two open ends.Treating the mechanics of fullerenes inside nanotube can be preformed by different methods of simulation. One of the most popular of these methods is Molecular Dynamics (MD) [4]. Molecular Dynamics simulation, used here, is a technique for computing equilibrium and dynamic properties of a classical many-body system. Newton's equations of motion are solved numerically, and macroscopic properties of the system are measured by applying statistical mechanics principles. The key ingredients in carrying out a molecular dynamics simulation include modeling the intermolecular interactions, the boundary conditions, and the integration algorithms [5].In this paper, by means of Velocity-Verlet method in MD simulation, and Lennard-Jones potential function as the model of intra-molecular interaction, the effect of boundary conditions on the frequency of the oscillations of a fullerene and its maximum velocity inside the nanotube are studied