Using molecular simulation, the adsorption and self-diffusion of diatomic nitrogen molecules inside a single-wall carbon nanotube were studied over a range of nanotube diameters (8.61 to 5.66Å) and loadings at 100 and 298K. The N adsorption energy was found to increase as the nanotube diameter was reduced towards the molecular diameter of nitrogen. A discrete organization of the nitrogen into adsorbed layers was observed at high loadings. This followed a regular progression which was governed by geometric considerations. The formation of an adsorbate core at the center of the nanotube was found to increase the self-diffusion of nitrogen. A so-called worm-like phase was found for adsorbed nitrogen in a (15,0) carbon nanotube at high loadings at 100K.

Adsorption and Diffusion of Molecular Nitrogen in Single Wall Carbon Nanotubes. G.Arora, N.J.Wagner, S.I.Sandler: Langmuir. 2004, 20[15], 6268-77