Vibrational and electronic spectra of some binuclear uranyl fluoride complexes

Abstract

Infrared, Raman, luminescence and electronic absorption spectra have been recorded at temperatures down to 4 K for K₅(UO₂)₂F₉, M₄(UO₂)₂F₈· 2H₂O, M₂(UO₂)₂F₆(OH₂)₂(M = Cs, Rb) and the deuterated analogues. A coupling of vibrational, but not of electronic motions is detected and the vibrational data are interpreted under unit-cell group-selection rules. The spectra are compared with those of the parent UO₂F^3–₅ ion in K₃UO₂F₅. Assignments for characteristic U—OH₂ modes of vibration in M₂(UO₂)₂F₆(OH₂)₂ are given.