Raman spectroscopic study of sodium chloride water solutions

The Raman spectra of NaCl water solutions have been studied in the concentration range between 0 and 3.3 M using a difference technique. The temperature dependence of the spectral profiles observed for the O-H stretching in the high frequency region (between 2500 and 4000 cm(-1)) was also investigated in the narrow interval around a room temperature. Although the considered bandshape is not of a simple kind, the measured I-d/I-0 ratio plotted versus NaCl concentration and temperature fits a straight line in both diagrams very satisfactorily. The linear dependence of I-d/I-0 versus NaCl molarity was checked in the study of natural seawater samples for which discrepancies were found. These deviations were attributed to other organic and inorganic dissolved components in the seawater. (C) 2000 Elsevier Science B.V. All rights reserved.