Dynamics of He/C₆₀ flow inside carbon nanotubes

Future nanotechnology applications are likely to involve reactive or non-reactive species carried along a fluid stream. We have performed several molecular dynamics simulations of a buckyball, C₆₀, cage or idealized atom in a helium fluid flowing axially inside a carbon nanotube. The fluid was started at some initial velocity and both the fluid and buckyball allowed to recycle axially via minimum image boundary conditions. A buckyball introduced into the feedstream (started at zero velocity) usually reached fluid velocity within 5 ps. Leakage rates of helium past the C₆₀ depended on the nanotube diameter and fluid velocity. These leakage rates and other important features of the dynamics changed significantly when C₆₀ was modelled as an idealized atom or when the nanotube was held rigid, suggesting that simulations of fluid dynamics inside nanomachines should be fully dynamic and atomistic.