Molecular Dynamics Study of Relaxation Modes of a Single Polymer Chain

Relaxation modes and rates of a single polymer chain with the excluded volume interaction is studied by molecular dynamics simulations. The variational method for the estimation of the relaxation modes and rates proposed by Takano and Miyashita [J. Phys. Soc. Jpn. 64 (1995) 3688] is generalized to cases where the detailed balance condition is not satisfied and applied to the results of the present simulations. The relaxation modes and rates estimated by the generalized method describe the behaviors of the autocorrelation functions of relative velocities and relative positions of the segments well. For a polymer chain with N segments, the behavior of the pth slowest relaxation rate λ_p with p/N ≪ 1 is consistent with the theoretical prediction λ_p ∝ (p/N)^2v+1, where v is the exponent for the size of a polymer chain in good solvent.