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
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.