CALCULATION OF THE EQUILIBRIUM CON-STANTS OF U(Ⅳ)-U(Ⅵ) ELECTRON EXCHANGE REACTIONS FROM ISOTOPE SHIFTS OF TRI-ALKYL PHOSPHATE SOLID CHLORO COMPLE-XES MEASURED BY I. R. SPECTRA

The isotope frequency shifts of the uranous and uranyl chloro solid complexes with three kind of trialkyl phosphate (TMP, TEP, TBP) are measured by I. R. spectrometry. The isotope shifts of uranyl chloro solid complexes are 0.87-1.18 cm-1 and the value from theoretical calculation is 0.70 cm-1. The isotope shifts of uranous complexes are 0.05-0.18 cm-1, and the calculated value is 0.16 cm-1.From the above data the equilibrium constants of the U(Ⅳ)-U(Ⅵ) electron exchange reactions are obtained in the range of 1.0013-1.0018 for these systems.The influence of the donor ligands on the effect of isotope shift is discussed.