Speciation and Coordination Chemistry of Uranyl(VI)−Citrate Complexes in Aqueous Solution
- 18 September 2003
- journal article
- Published by American Chemical Society (ACS) in Inorganic Chemistry
- Vol. 42 (21) , 6793-6800
- https://doi.org/10.1021/ic0341800
Abstract
The pH dependence of uranyl(VI) complexation by citric acid was investigated using Raman and attenuated total reflection FTIR spectroscopies and electrospray ionization mass spectrometry. pH-dependent changes in the νs(UO2) envelope indicate that three major UO22+−citrate complexes with progressively increasing UO bond lengths are present over a range of pH from 2.0 to 9.5. The first species, which is the predominant form of uranyl(VI) from pH 3.0 to 5.0, contains two UO22+ groups in spectroscopically equivalent coordination environments and corresponds to the [(UO2)2Cit2]2- complex known to exist in this pH range. At pH values >6.5, [(UO2)2Cit2]2- undergoes an interconversion to form [(UO2)3Cit3]3- and (UO2)3Cit2. ESI-MS studies on solutions of varying uranyl(VI)/citrate ratios, pH, and solution counteranion were successfully used to confirm complex stoichiometries. Uranyl and citrate concentrations investigated ranged from 0.50 to 50 mM.Keywords
This publication has 30 references indexed in Scilit:
- Investigation of reduction of Cu(II) complexes in positive‐ion mode electrospray mass spectrometryRapid Communications in Mass Spectrometry, 2001
- Infrared and Raman spectra of uranyl(VI) oxo-hydroxo complexes in acid aqueous solutions: a chemometric studyVibrational Spectroscopy, 2000
- Infrared and Raman spectroscopic study of uranyl complexes: hydroxide and acetate derivatives in aqueous solutionVibrational Spectroscopy, 1998
- Metal-ligand redox reactions in gas-phase quaternary peptide-metal complexes by electrospray ionization mass spectrometryInternational Journal of Mass Spectrometry and Ion Processes, 1997
- A Database for the Static Dielectric Constant of Water and SteamJournal of Physical and Chemical Reference Data, 1995
- Photodegradation of Uranium-Citrate Complex with Uranium RecoveryEnvironmental Science & Technology, 1994
- The uranium trioxide-water systemJournal of Inorganic and Nuclear Chemistry, 1973
- The Chlorination of Metals in the Presence of a Donor Solvent1Journal of the American Chemical Society, 1954
- The Uranyl: Citrate System. II. Polarographic Studies of the 1:1 Complex1Journal of the American Chemical Society, 1951
- The Crystal Structure of Sulfamic Acid1Journal of the American Chemical Society, 1951