LUMINESCENCE OF FROZEN-SOLUTIONS OF CURIUM(III) WITH POLYTUNGSTATE ANIONS

Spectra and lifetimes for luminescence from solutions of complexes frozen at 77 K are measured. Complexes of curium(III) with P2W17O61(10-) luminesce brightly at 77 K although luminescence from nitrogen laser excitation in the liquids is not found. Luminescence of all remaining complexes at 77 K increases by at least several times compared to the liquids. The luminescence is quickly quenched as the solution freezes. The quenching quickly decreases as the temperature of the frozen solution is decreased. At 77 K, it almost disappears for the majority of complexes. The enhanced quenching on freezing and the relatively short luminescence lifetime at 77 K are associated with changes in the complex structures on freezing.