Dielectric properties of normal supercooled water obtained in alcohol/water mixtures

The complex permittivity of (alcohol)/sub x//(water)/sub 1-x/ mixtures was studied between 1 mHz and 10 MHz, from ambient down to the glass transition temperature, in the molar fraction range 0.1or=0.1) eliminates the anomalous properties of pure water, and further explorations at x=0 lead to the normal part of static permittivity and relaxation time of supercooled water down to its glass transition temperature T/sub g/=-135 degrees C. These calculated values are nearly independent of the alcohol used. The static permittivity between +100 and -135 degrees C can be adjusted by the relation in /sub s/=-22.2+29950/T, which agrees well with the random network model. The dielectric relaxation time can be fitted to the free-volume percolation model of M.H. Cohen and G.S. Grest (1984). As long as the solutions remain homogeneous, dielectric spectra exhibit a single absorption peak, which broadens near the glass transition temperature.<>