STUDY OF THE MULTIPLICITY OF DIELECTRIC RELAXATION TIMES IN ICE AT LOW TEMPERATURES.

By the use of several experimental techniques offered by the method of thermally stimulated depolarization (TSD), it was demonstrated that the low temperature TSD peak of polycrystalline ice Ih, which is due to the dipolar polarization mechanism of ice in this temperature range, consists of a secondary component at 108K and a main peak at 119K. The characteristics of the secondary component are : activation energy W=0.24eV, pre-exponential factor in the Arrhenius equation τo=7.4x10-9s and dielectric strength ∼4% of the whole peak. The main peak can be described by a dielectric relaxation mechanism characterised by a continuous distribution of relaxation times, with both W and to being distributed parameters, with mean values of 0.31eV and 5x10-12s respectively. An attempt has been made to interpret the results at the molecular level