Relaxation Dynamics and Mesoscopic Feature of Glass Forming Glycerol-Water mixtures

The main goal of this particular research is an understanding of dynamics and structure of hydrogen bonding liquids and the study of fluctuations and transport in the hydrogen-bonded network at the mesoscopic scale. Broadband Dielectric Spectroscopy will be used in conjunction with calorimetric and high precision density measurements. That allows to study dynamics of the systems in the entire frequency (time) range from 10 GHz to 1 mHz (total broader than 13 orders). At first, glycerol-water mixtures will be studied as an excellent model system. Systematic study covering with wide frequency, temperature, and concentration ranges will clarify the mechanisms of slow- and fast- dynamics through dc-conductivity, main relaxation process and high frequency excess wing that can be relating to the cage dynamics. The fact that all normalized spectra traced the same single curve indicates that dielectric response at both high and low frequencies follows the same temperature dependence of the main relaxation process. Therefore, it leads to the hypotheses that the relaxation mechanism of the excess wing, the main process and dc-conductivity are based on the same origin in glycerol-rich mixtures.

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Fig.5. Schematic presentation of ice formation in W–G mixtures in the critical concentration range.