A Molecular Dynamics Simulation Study of the Self-Diffusion Coefficient and Viscosity of the Lennard–Jones Fluid

摘要

Self-diffusion coefficients and viscosities for the Lennard–Jones fluid were obtained from extensive equilibrium molecular dynamics simulations using the Einstein plot method. Over 300 simulated state points cover the entire fluid region from the low-density gas to the compressed liquid close to the melting line in the temperature range T*=Tk/ε=0.7 to 6.0. The translational–translational, translational–configurational, and configurational–configurational contributions to the viscosity are resolved over this broad range of fluid states, thus providing coherent insight into the nature of this transport property. The uncertainties of the simulation data are conservatively estimated to be 0.5% for self-diffusion coefficients and 2% for viscosities in the liquid region, increasing to 15% at low-density gaseous states.