Electrochemical generation and spectrophotometric study of solute species in molten fluoride media

Abstract

Studies of the electrochemical generation and simultaneous spectrophotometric observation of several solute species in molten fluoride media were carried out. Attempts were made to generate Mn(III), Co(III) and Cu(III) in molten LiFNaFKF from the divalent or metallic state. The generation and spectral observation of Mn(III) was possible; the generation of Co(III) was inferred from electrochemical results; the generation of Cu(III) was not possible under our experimental conditions. Experimental results along with reasons for obtaining these results are discussed. The absorption spectra of Mn(II), Mn(III) and Cu(II) in molten LiFNaFKF at 500°C are presented. The spectra indicate that all these ions are situated at or very near octahedral symmetry in this melt. Molar absorptivities of the most sensitive d-d transition are given in each case.