Dielectric relaxation of aqueous asparagine [C₄H₈N₂O₃] was studied over a different temperature range of (5 to 25°C), and at various molar concentrations of (0.05, 0.10, 0.15, 0.20) g/mol, using TimeDomain Reflectometry (TDR) in the frequency range of 10 MHz to 50 GHz. Whereas calculating the dielectric parameters including dielectric strength (Δε), dielectric constant (ε°), and relaxation time (τ), was obtained from complex permittivity spectra ε*(ω), using the Cole-Davidson model fit method. Using these parameters, thermodynamic values parameters are determined such as free energy (ΔF), activation entropy (ΔS) and activation enthalpy (ΔH), in order to predict the intermolecular interaction at the molecular level of aqueous asparagine solution, in this study, all the studied concentrations show a systematic change in dielectric parameters with temperature and concentration. It was observed that the peak of dielectric loss for all studied temperatures shifts towards lower frequency with increasing concentration. Furthermore, the dielectric constant (ε°), decreases at lower concentrations and starts to increase at higher concentrations. The dielectric constant was also affected by temperature, as its value decreased with increasing temperature. At that time, an increase in the relaxation time (τ) was observed towards the higher concentration of the solute molecule. However, it seems that the relaxation time decreases with the increase in the studied temperature.

Dielectric Relaxation, Asparagine, Thermodynamic Parameter, Time Domain Reflectometry (TDR)