THE RELATIONSHIP BETWEEN THE POLEY ABSORPTION AND FRACTIONAL POWER-LAW RELAXATION IN THE CLUSTER MODEL

Citation
La. Dissado et Jm. Alison, THE RELATIONSHIP BETWEEN THE POLEY ABSORPTION AND FRACTIONAL POWER-LAW RELAXATION IN THE CLUSTER MODEL, Journal of molecular liquids, 56, 1993, pp. 295-316
Citations number
37
Categorie Soggetti
Physics, Atomic, Molecular & Chemical
ISSN journal
01677322
Volume
56
Year of publication
1993
Pages
295 - 316
Database
ISI
SICI code
0167-7322(1993)56:<295:TRBTPA>2.0.ZU;2-N
Abstract
The response function derived for the cluster model possesses an analy tical form over the whole time range form zero to infinity. Previous w ork has concentrated upon its behaviour in the non-inertial (relaxatio n) regime where it predicts a non-Debye decay consisting in general of two power laws, namely t(-n) at t < 1/omega(p) and t-(m+1) for t > 1/ omega(p) with omega(p) the loss peak frequency. Here it is shown that the exact response function of this model gives an absorption peak in the inertial region (Poley absorption) as well as a relaxation loss pe ak. Furthermore the relative magnitude of the predicted Poley absorpti on is shown to decrease with the value of the exponent n (< 1) appropr iate to the relaxation peak, leading to an isolated Debye peak for n = 0. A comparison with the experimental data will be made and the relat ionship between the Cluster Model and other models for the Poley absor ption discussed.