RAMAN INTENSITIES OF LIQUIDS - ABSOLUTE SCATTERING ACTIVITIES AND ELECTROOPTICAL PARAMETERS (EOPS) OF ARSENATE AND SELENATE IONS IN AQUEOUS-SOLUTIONS

Absolute Raman scattering activities of aqueous solutions of sodium arsenate and sodium selenate have been measured against NaClO4 as an external standard. Electro-optical parameters (EOPs) for the As-O and Se-O bonds were calculated. Changes of the previously published force fields (GVFF) were necessary to adjust the eigenvectors to the experimental frequencies and intensities in aqueous environment. Equilibrium bond polarizabilities were estimated from refractive index measurements in connection with Raman intensities of bending modes. The EOPs of these two isoelectronic compounds are discussed in comparison with the series phosphate, sulphate, perchlorate.