SPECIATION OF PLUTONIUM IN WATER

Abstract

Author Institution: Department of Chemistry, The Ohio State University; Chemical Technology Division/Materials Science Division, Argonne National Laboratory; Department of Chemistry, The Ohio State UniversityThe speciation of plutonium in water was modeled using density functional theory (DFT) methods. Aqueous plutonium exists in four oxidation states: $+3, +4, +5$, and $+6$. The first two forms exist as the bare ions, but the $+5$ and $+6$ states exist as $(PuO_{2})^{+}$ and $(PuO_{2})^{2+}$ species, respectively. The coordination number for the number of water molecules around each of these species is determined and compared to experiment - which uses XANES (X-ray Absorption Near-Edge Spectroscopy) and cXAFS (extended X-ray Absorption Fine Structure) spectroscopy. The DFT calculations include generalized gradient corrections