Note on the number dependence of nonequilibrium molecular dynamics simulations of the viscosity of structured molecules.

Nonequilibrium molecular dynamics simulations have been performed for a system of 512 four-site models representing n-butane molecules. The results are compared to simulations previously reported for 125 molecules to check a recently reported number dependence in such simulations. A small system size dependence was observed at low shear rates, but the rheological behavior is not affected. Considerably greater certainty is obtained using larger systems. [ABSTRACT FROM AUTHOR]