A quantitative theory of linear chain polymer dynamics in the melt .2. Comparison with simulation data

Estimates are evaluated for all constants in the theory of polymer dynamics developed in the preceding paper. These theoretical estimates are employed in calculations on the many chain systems simulated previously by Kremer and Grest and by Paul and co-workers. The agreement between the theoretical calculations and the simulations of Kremer and Grest is found to be very good for the bead mean squared displacement, The theoretically evaluated center of mass mean squared displacement is in good qualitative agreement with the Kremer-Grest simulations, although there are quantitative differences. Good qualitative agreement with the simulations of Paul and co-workers is also obtained. It is shown that quantitative agreement can be obtained with modest changes in the theoretical estimates of a few of the constants in the theory. (C) 1996 American Institute of Physics.