Cole-Davidson dynamics of simple chain models.

摘要: Rotational relaxation functions of the end-to-end vector short, freely jointed and rotating chains were determined from molecular dynamics simulations. The associated response obtained one-sided Fourier transform functions. Cole–Davidson function was used to fit with extensive use being made Cole–Cole plots in fitting procedure. For systems studied, provided remarkably accurate fits [as compared Kohlrausch–Williams–Watts (KWW) function]. only appreciable deviations simulation results high frequency limit due ballistic or free rotation effects. accuracy appears be result transition time domain stretched exponential behavior at intermediate single long time. Such a can explained terms distribution times well-defined longest Since has sharp cutoff (while KWW does not), it makes sense that would provide better frequency-domain description than does.