GENERATION OF CHARGE-CARRIERS AND FORMATION OF ANTISYMMETRIC DOUBLE ELECTRIC LAYERS IN GLYCERIN

The effect of increasing (by more than one order of magnitude) of the conductivity of glycerine under the action of a low-frequency electric held (10(-4)-10(-3) Hz) and heating is discovered and investigated. T he transition into the high-conductivity state is accompanied by forma tion of asymmetric double electric layers at the electrodes. Parameter s of the electric barrier at the interface are determined. For example , for the sample with thickness 18 mu m at the temperature 325 K, the height of the potential barrier is 0.4 V, the thickness is 2.1 nm, the concentration of ionized centers is 3 x 10(26) m(-3). The transition into the mon conductive state can be induced by desorption of ions fro m the electrode surface. The properties of glycerine are investigated for the both low and high-conductive states by low frequency dielectri c spectroscopy. The dispersion of components epsilon' and epsilon '' o f the complex dielectric permittivity for the both states is described by the Debye equation modified by Cole-Cole. The dielectric relaxatio n time tau and the thickness of the double electric layer WC-C, where the redistribution of charges takes place, are measured. The transitio n into the high-conductivity state is characterized by the decreasing (more than one order) of tau, its activation energy and WC-C Compariso n of the obtained data with the data for the Liquid crystal mixture 12 82 suggests that the dispersion of epsilon' and epsilon '' is induced by redistribution of charges between the bulk and the interface. (C) 1 998 American Institute of Physics.