Measurement of the Raman spectrum of liquid water

The Raman spectrum from water was obtained for a range of conditions from ambient to above the critical point, 256 bar and 400 °C. A fluorescence-free sapphire high-pressure Raman cell was employed with which the Raman spectra from water were examined between 30 and 4000 cm−1. Computer deconvolution of the Raman OH-stretching contours allowed the hydrogen bond strength to be determined from the integrated component intensity ratios by use of the van’t Hoff relationship. This procedure yielded a hydrogen bond enthalpy of 2.53±0.10 kcal/mol which is in excellent agreement with previously reported values.