Best Estimation of Transport Coefficients by Time Correlation Functions without Model-dependence in Fluctuation-based Equilibrium Simulation Method

The transport coefficients, such as the diffusion coefficient and the shear viscosity, are important material properties calculated in computer simulations. It is proved in the letter that the criterion for the best estimation of viscosity as an example of transport coefficients by using the Green-Kubo formula without any anticipated models. The related algorithm is shown by the estimation of viscosities of PEO solutions by using molecular dynamics simulation as a test vehicle. The algorithm can be used in the simulations of complex systems with a long tail of correlations typically found in the macromolecular and biological simulation systems.