title: Determination of successive complexation constants in an ionic liquid: complexation of UO(2)(2+) with NO(3)(-) in C(4)-mimTf(2)N studied by UV-Vis spectroscopy.
abstract: The complexation of UO(2)(2+) with NO(3)(-) has been investigated in the ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide by UV-vis spectroscopy at T = 18.5 degrees C. The complexation is evidenced through the appearance of four peaks at 425, 438, 453, and 467 nm. EXAFS data indicate that the trinitrato complex, UO(2)(NO(3))(3)(-), is dominating the speciation for a reagent ratio of [NO(3)(-)]/[UO(2)(2+)] > 3. Assuming three successive complexation steps, the conditional stability constants are calculated, the individual absorption spectra are derived, and a speciation plot is presented.
authors.affiliation: IPHC, UMR 7178 CNRS-IN2P3 et Université de Strasbourg, 23 rue du Loess, 67037 Strasbourg cedex 2, France.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Georg
authors.forename: Isabelle
authors.initials: I
authors.lastname: Billard
authors.forename: Ali
authors.initials: A
authors.lastname: Ouadi
authors.forename: Clotilde
authors.initials: C
authors.lastname: Gaillard
authors.forename: Laetitia
authors.initials: L
authors.lastname: Petitjean
authors.forename: Michel
authors.initials: M
authors.lastname: Picquet
authors.forename: Vitaly
authors.initials: V
authors.lastname: Solov'ev