A spiral diffusion path for non-spherical organic molecules in carbon nanotubes was studied. Classical molecular dynamics simulations and density functional theory calculations were used to investigate the diffusive behavior of ethane and ethylene in single-walled carbon nanotubes. It was concluded that the simulation and calculations quantified the level of alignment of C-C bonds in small non-spherical hydrocarbon molecules with C-C bonds in carbon nanotube walls that maximized molecule-nanotube interactions.

Predictions of a Spiral Diffusion Path for Nonspherical Organic Molecules in Carbon Nanotubes. Z.Mao, S.B.Sinnott: Physical Review Letters, 2002, 89[27], 2783011-4