The study of aqueous isopropanol solutions at various concentrations: low frequency Raman spectroscopy and molecular dynamics simulations

The low-frequency Raman spectra of aqueous isopropanol mixtures at different proportions have been recorded. The influence of the isopropanol concentration on the position of the peak at (ν) over bar (2) = 190 cm(-1) associated to hydrogen bond between water molecules has been analyzed. The small shift to lower frequencies of the (ν) over bar (2) band indicates that isopropanol has a small effect of a structure breaker of hydrogen bond between water molecules. This result is correlated to the degree of self aggregation at a microscopic level of isopropanol. (C) 2003 Elsevier Science B.V. All rights reserved.