First Evidence of a Water-Soluble Plutonium(IV) Hexanuclear Cluster

The singular Pu-IV hexanuclear cluster [Pu-6(OH)(4)O-4](12+) stabilized by 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) ligands was structurally characterized for the first time both in the solid state and in water solution by using X-ray diffraction and X-ray absorption and UV/Vis spectroscopy. The stability of this cluster in water and its high solubility over a large pH range are of upmost importance for plutonium environmental speciation with potential applications in a related migration model.