BRILLOUIN AND RAMAN-SCATTERING FROM LIQUID WATER

Recent experimental results obtained on normal and deuterated water using light-scattering spectroscopy from Brillouin to librational Raman frequencies are reviewed. Particular attention is devoted to the librational mode region and to the Rayleigh wing where both new measurements (including depolarization ratio measurements and absolute intensities analysis) and computer simulation have pointed out the importance of "interaction-induced" scattering contributions in interpreting quantitatively this low-frequency part of the spectrum. The agreement between experimental and simulated data extends up to the 400 wavenumbers band, excluding the presence of direct electronic disturbances created by hydrogen-bond formation dynamics in this spectral region.