Effect of electrolyte concentration on the Raman spectra of water in aqueous solutions

• DOI: 10.1002/jrs.1250170202
• Publication Date: 2005-05-28T19:27:26Z
• Authors: F. Rull; J. A. de Saja
• Keywords: 0103 physical sciences; 02 engineering and technology; 0210 nano-technology; 01 natural sciences; 3. Good health

Abstract Polarized Raman spectra of water in the ν(OH) and δ(OH 2 ) regions have been recorded for aqueous solutions electrolytes types AB (A = Li, Na, K, Ca; B Cl, Br, I, NO 3 over a wide concentration range. Variations frequencies, intensities, band shapes widths with changes nature ions are discussed. The isotropic anisotropic components intensity analysed as function concentration. It is found that 45(a') approximately independent of, or decreases slightly with, alkali metal halides whereas nitrates it increases linearly 3(γ′) very slowly both nitrates. These results compared those obtained pure when temperature varied range −20 to 120°C. Despite difference two perturbation (ionic thermal), all can be interpreted terms modifications intra‐and inter‐molecular couplings Fermi resonance between vibrational modes molecules.