Fully atomistic simulations were used to study the diffusion of alkane molecules, having various chain lengths in single-wall carbon nanotubes with various diameters. The self-diffusion coefficient, mean-square gyration and bond-orientation order parameter of the alkane molecule, and the average intermolecular interaction energy per segment between single wall carbon nanotube and alkane, were calculated. The structure of alkanes in single-wall carbon nanotubes was characterized in terms of the radial distribution function. The results showed that the self-diffusion coefficient was related to the nanotube diameter. The component of mean-square gyration in the z-direction scaled with the alkane chain length in single-wall carbon nanotubes (9,9), as N1.07. This was in good agreement with the predictions of scaling theory for polymers. The results showed that the nanotube diameter and alkane chain length were important factors affecting the behavior of one-dimensional confined alkanes.

Diffusion of Single Alkane Molecule in Carbon Nanotube Studied by Molecular Dynamics Simulation. Yang, H., Liu, Y., Zhang, H., Li, Z.S.: Polymer, 2006, 47[21], 7607-10