Equilibrium and relaxation dielectric properties of 1,2-ethanediol

Data on the static relative permittivity (?_s) of 1,2-ethanediol over a temperature range of 243 to 423 K were examined within the framework of the Onsager-Kirkwood-Fröhlich theory. An analysis of the dispersion of the complex relative permittivity ?^*(ω) of ethanol using the Davidson-Cole and Vogel-Fulcher-Tammann was performed empirical equations and the Adam-Gibbs molecular-kinetic theory. The correlation factor g _exp, relaxation time τ _DC, and distribution parameter β were determined. It was established that the parameter β increases from 0.72 to 0.845 as the temperature rises from 243 to 453 K, in contrast to the previous studies, in which it was set temperature-independent. The parameters of the Vogel-Fulcher-Tammann were found to be T ₀₁ = 93.809 K, τ _0VFT1 = 6.96 × 10^?14 s, and U _∞VFT1 ^# = 12.73 kJ/mol. Based on the Adam-Gibbs equation, the number of molecules involved in an elementary event of cooperative structural rearrangement was estimated to be z ^* = 3.1?2.4 within 161–186 K and z ^* = 1.63?1.26 within 243–453 K.