title: Structure of the UO2 2+-SO 4 2- ion pair in aqueous solution.
abstract: The structure of the ion pairs formed in aqueous uranyl sulfate solutions has been investigated with high-energy X-ray scattering. Sulfate binds to the uranyl as a monodentate ligand in equimolar solutions. The geometry of the ion pair is very similar to configurations found in crystalline structures; in particular, the U-O-S angle is bent in solution as well as in the solid state. It can therefore be concluded that an U-O-S angle of 143 degrees is an intrinsic property of the uranyl sulfate bond and not due to packing effects or interaction with the water in the primary solvation shell.
authors.affiliation: Chemistry Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439.
authors.forename: J
authors.initials: J
authors.lastname: Neuefeind
authors.forename: S
authors.initials: S
authors.lastname: Skanthakumar
authors.forename: L
authors.initials: L
authors.lastname: Soderholm