THE WILLIAMS-WATTS DEPENDENCE AS A COMMON PHENOMENOLOGICAL APPROACH TO RELAXATION PROCESSES IN CONDENSED MATTER

The Williams Watts (WW) relaxation function has been widely used to de scribe the relaxation behaviour of many systems. In the present work t he range of applicability of the WW response was extensively tested by the analysis of experiments in both the time and the frequency domain s. On the other hand, the analysed experiments covered a wide time-sca le for the characteristic relaxation times. Some related topics were a lso considered, i.e. our procedures in obtaining the associated activa tion energy spectra or the distribution of relaxation times. The relat ionship between time-domain and frequency domain relaxation responses was also analysed. In light of our results the universality of the WW response, appears to be good at least for the time-scales and the diff erent probes covered by our experiments.