Dielectric study of X type zeolites: evidence for cation correlated motions

we have previously pointed out the existence of correlated movements for the cations in X-type zeolites. In this paper, we intend to show from the analysis of the dielectric relaxation spectra that the correlation is limited to the cations present in a microscopic sphere (cluster) of radius "δ" .The value of "δ" is found to be at least 8Å for X-type zeolites containing essentially monovalent cations. As a consequence, dielectric relaxation, if performed in a sufficiently wide frequency range, can give information on zeolites at a microscopic level