Liquid and Ice Water and Glycerol/Water Glasses Compared by Infrared Spectroscopy from 295 to 12 K

Abstract

Infrared absorption spectra for liquid and ice H2O and D2O and for protonated and deuterated glycerol/water glasses are compared in the spectral range of 1000−4000 cm-1 and the temperature range of 295−12 K. As temperature decreases, the absorbance bands of the OH and OD stretching modes of glycerol/water solution shift to lower frequency and the band intensifies and narrows. The center of the absorption band for OH stretch for glycerol/D2O/H2O solution (60/32/8 v/v) is at 3364 cm-1 at 295 K and at 3277 cm-1 at 25 K. The full width at half-maximum (fwhm) of the band is 259 cm-1 at 295 K and 186 cm-1 at 25 K. The width of the OH stretch band for D2O that is doped with H2O is 193 cm-1 in liquid (295 K) and 24 cm-1 in ice (12 K). The broader width for the OH stretch at 12 K for glycerol/water relative to that seen in ice is consistent with inhomogeneous broadening due to the glassy nature of glycerol/water solutions. The HOH and DOD bending (scissoring) bands for water in glycerol shift to higher frequency, ...