A study of the dielectric behavior and the liquid structure of a ternary solvent system

The static dielectric constant of the {DMF(1) + ME(2) + DME(3)} ternary mixtures was measured as a function of temperature (25 less than or equal to t/degreesC less than or equal to 80) and composition, over the whole mole fraction range 0 less than or equal to x(1),x(2),x(3) less than or equal to 1. The experimental values were processed by an empirical equation accounting for the dependence epsilon = epsilon(T, phi(i)), where phi(i) is the volume fraction of the components. A comparison between calculated and experimental data shows that this fitting relationship can be effectively employed to predict epsilon values in correspondence to experimental data gaps. Starting from the experimental measurements, some derived quantities such as molar polarisation (P), and excess counterpart (P-E) were obtained. Both the excess properties, epsilon(E) and P-E, take values partly positive and partly negative under all experimental conditions. The values of the excess quantities are indicative of the presence of specific interactions among different components in the mixtures.