RELAXATION FUNCTION FOR A SYSTEM WITH A BOUNDED BROAD DISTRIBUTION OF RELAXATION-TIMES

The long-time limit of the relaxation function for system with a broad uniform but bounded continuous distribution of relaxation times is shown to be of the Yukawa form. This is in contrast to the single or multiple exponential functions often used to extract relaxation time constant tau from fitting experimental or numerical simulation data. Although such fittings will still obtained the correct tau in the long-time limit, our results predict a logarithmic term, which will slow the convergence.