Excess wing in the dielectric loss of glass-forming ethanol: A relaxation process

A detailed dielectric investigation of liquid, supercooled liquid, and glassy ethanol was performed, extending the frequency and temperature range of previous investigations. The results reveal a third relaxation process, in addition to the two processes already known. In this respect the relaxational behavior of ethanol resembles that of other primary alcohols. The relaxation time of this process exhibits strong deviations from thermally activated behavior. Most important, this process is the cause of the apparent excess wing, which was claimed to be present in the dielectric loss spectra of glass-forming ethanol. In addition, marked deviations of the spectra of ethanol from the scaling proposed by Dixon and Nagel have been detected.