A structural and spectroscopic study of the first uranyl selenocyanate, [Et4N]3[UO2(NCSe)5]

Abstract

The first example of a uranyl selenocyanate compound is reported. The compound [Et4N]3[UO2(NCSe)5] has been synthesized and fully characterized by vibrational and multinuclear (1H, 13C(1H) and 77Se(1H)) NMR spectroscopy. The photophysical properties have also been recorded and trends in a series of uranyl pseudohalides discussed. Spectroscopic evidence shows that the U-NCSe bonding is principally ionic. An electrochemical study revealed that the reduced uranyl(V) species is unstable to disproportionation and a ligand based oxidation is also observed. The structure of [Et4N]4[UO2(NCSe)5][NCSe] is also presented and Se...H-C hydrogen bonding and Se... Se chalcogen-chalcogen interactions are seen.