THE CALCULATION OF VISCOSITY OF LIQUID N-DECANE AND N-HEXADECANE BY THE GREEN-KUBO METHOD

This short commentary presents the result of long molecular dynamics s imulation calculations of the shear viscosity of liquid n-decane and n -hexadecane using the Green-Kubo integration method. The relaxation ti me of the stress-stress correlation function is compared with those of rotation and diffusion. The rotational and diffusional relaxation tim es, which are easy to calculate, provide useful guides for the require d simulation time in viscosity calculations. Also, the computational t ime required for viscosity calculations of these systems by the Green- Kubo method is compared with the time required for previous non-equili brium molecular dynamics calculations of the same systems. The method of choice for a particular calculation is determined largely by the pr operties of interest, since the efficiencies of the two methods are co mparable for calculation of the zero strain rate viscosity.