Simulation of a relativistic soliton model of crystalline polymer dynamics

The study of the sine-Gordon soliton model of the dielectric α relaxation in crystalline polymers is continued. We examine the intermediate range of the coupling constant, which is essentially the ratio of intramolecular to intermolecular interaction strengths, via another stochastic molecular dynamics computer simulation. The model is that of Currie et al. of the soliton as a pseudo-relativistic particle moving in an effective periodic potential. Comparison with the previous sine-Gordon chain simulation results in increasingly poor agreement with decreasing coupling constant, probably because of the neglect of multiple soliton effects. However, we find in the process the interesting result that relativity lowers the effective rate constant in such barrier-crossing problems. Finally, we also note that the continuum limit theory which is successful for nonpolar polymers may apply to other soliton-related physical systems as well.