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The crystallization kinetics of glassy Se and binary Se₉₈M₂ (M=Ag, Cd, Zn) alloys have been studied at different heating rates (5, 10, 15, 20 Kmin^-1) using Differential Scanning Calorimetric (DSC) technique. The crystallization temperature (<i>T_c</i>) is determined from exothermic peak obtained in DSC scans of present samples. The variation in peak crystallization temperature (<i>T_c</i>) with the heating rate (<i>β</i>) has been used to investigate the growth kinetics using Kissinger, Augis-Bennet and Matusita-Sakka models. The activation energy of crystallization (<i>E_c</i>) has been found to increase with Ag additive and to decrease with Zn and Cd additive. The value of various kinetic parameters such as rate constant (<i>K_p</i>), Avrami index (<i>n</i>), thermal stability (<i>S</i>) and Hruby number (<i>H_r</i>) have been calculated under non-isothermal mode. The maximum change in different kinetic parameters has been found after the incorporation of Ag additive

A detailed study of conduction mechanism of glassy Se 70 Te 30 and Se 70 Te 28 M 2 (M = Ag, Zn and Cd) alloys has been carried out in terms of dielectric properties and a.c. conductivity. Temperature and frequency dependent dielectric constant, dielectric loss and ac for the same system were measured in the frequency spectrum, 1 kHz to 1 MHz and temperature range, 303-338 K. The a.c. conductivity (ac) is found to be proportional to ω s (s < 1). The temperature dependence of both a.c. conductivity and frequency exponent (s) is reasonably well interpreted by the correlated barrier hopping (CBH) model. We showed that the bipolaron hopping is dominant over the potential barrier and estimated the density of defect states (DOS) at 10 kHz. We found a good agreement between bi-polaron conductivity and experimental results.