Solvation of Eu(III) and Tb(III) Ions in Anhydrous CH₃CN DMF

Abstract

Lanthanoid(III) ion solvation has been investigated by many different techniques. Few studies, however, have been performed in strictly anhydrous solvents, and the coordination number of these ions is not always established with certainty. We report here some results we obtained on the solvation of Eu(III) and Tb(III) ions in anhydrous acetonitrile, dimethylformamide, and in binary solvent mixtures. We have studied solutions of nitrate and perchlorate (0.0001–0.2 M) by means of conductimetry, vibrational spectroscopy, and fluorescence measurements which are very sensitive to changes in the first solvation sphere (1). The long fluorescence lifetimes reported in Table 1 reflect the very low water content of the salts (2) and solvents (3) used (no water quenching).