The knowledge of the diffusion coefficient of a molecule in dense fluids at a given density and temperature played an important role in many chemical processes. Molecular dynamics simulation was recognized as a useful tool to provide exact results of theoretical models, thus affording a database for the development of empirical models that could be readily accessible for engineering purposes. The aim of this work was to provide self-diffusion coefficient data from molecular dynamics simulation for freely jointed Lennard-Jones chain fluids of lengths 2, 4, 8 and 16 at the reduced densities ranging from 0.1 to 0.9 and at the reduced temperature interval of 1.5 to 4. Based upon both Chapman-Enskog formalism and molecular dynamics simulation data, an equation was proposed for calculating the self-diffusion coefficients of polyatomic fluids. The present model represented the self-diffusion coefficients with an absolute average deviation of 15.3%.

Molecular Dynamics Simulation Data of Self-Diffusion Coefficient for Lennard-Jones Chain Fluids. Reis, R.A., Silva, F.C., Nobrega, R., Oliveira, J.V., Tavares, F.W.: Fluid Phase Equilibria, 2004, 221[1-2], 25-33