EXAFS Determinations of Uranium Structures: The Uranyl Ion Complexed with Tartaric, Citric, and Malic Acids

• DOI: 10.1021/ic9508536
• Publication Date: 2002-07-26T05:30:15Z
• Authors: P. G. Allen; D. K. Shuh; J. J. Bucher; N. M. Edelstein; T. Reich; M. A. Denecke; H. Nitsche
• Keywords: Uranyl; Tartaric acid; Carboxylate

U LIII-edge EXAFS spectra were measured for 1:1 mixtures of the uranyl ion with tartaric, malic, and citric acids. The room-temperature these demonstrate characteristic uranium−oxygen interactions UO22+ also show a U−U interaction at 3.92 Å, indicating presence dimer. On basis models proposed by Martell et al. from earlier potentiometric titration experiments, it is concluded that dimer ligand-bridged species (UO2)2(L)2, in which bridging occurs through α-hydroxyl groups polycarboxylate ligands.