Low frequency depolarized light scattering from aqueous solutions of alkali halides

The depolarized scattering spectrum from 3 cm−1 to 300 cm−1 has been recorded for a range of aqueous solutions of alkali halides over a wide concentration range. The profile has been analysed in terms of two elastic bands which are essentially Lorentzian in shape and two inelastic bands at ∼60 cm−1 and ∼180 cm−1 which are described by a Lorentzian‐Gaussian product function. The relationship of the inelastic features to those previously obtained by band convolution is examined. It is shown that there is coupling between the broader elastic mode and that at 60 cm−1. This has the effect of strongly damping the motion responsible for the 60 cm−1 band. Variations in band width and intensity with change in concentration, cation and anion are discussed.