DEPENDENCE OF POLAROGRAPHIC BEHAVIOUR OF EUROPIUM FROM SOLVENT AND SUPPORTING ELECTROLYTE

Polarographic investigations on europium(III)perchlorate were carried out in acetonitrile, propanediol-1,2-carbonate, trimethylphosphate, N,N-dimethylformamide, N,N-dimethylacetamide and dimethyl sulfoxide. E1/2, the diffusion coefficients, the diffusion current constants and the reversibility or irreversibility of the electrochemical reactions are given. A linear relationship was found between E1/2 for the wave Eu(III)-Eu(II) and the donor number of the solvent investigated even when the supporting electrolyte contained a complexing anion. The donor strength of the anions and that of the solvent molecules increases in the following order: {Mathematical expression} © 1969 Springer-Verlag.