Comparative density functional study of the complexes UO2(CO3)(3) (4-) and (UO2)(3)(CO3)(6) (6-) in aqueous solution

With a relativistic all-electron density functional method, we studied two anionic uranium(VI) carbonate complexes that are important for uranium speciation and transport in aqueous medium, the mononuclear tris(carbonato) complex [UO2(CO3)(3)](4) and the trinuclear hexa(carbonato) complex [(UO2)(3)(CO3)(6)](6-). Focusing on the structures in solution, we applied for the first time a full solvation treatment to these complexes. We approximated short-range effects by explicit aqua ligands and described long-range electrostatic interactions via a polarizable continuum model. Structures and vibrational frequencies of "gas-phase" models with explicit aqua ligands agree best with experiment. This is accidental because the continuum model of the solvent to some extent overestimates the electrostatic interactions of these highly anionic systems with the bulk solvent. The calculated free energy change when three mono-nuclear complexes associate to the trinuclear complex, agrees well with experiment and supports the formation of the latter species upon acidification of a uranyl carbonate solution.     «

With a relativistic all-electron density functional method, we studied two anionic uranium(VI) carbonate complexes that are important for uranium speciation and transport in aqueous medium, the mononuclear tris(carbonato) complex [UO2(CO3)(3)](4) and the trinuclear hexa(carbonato) complex [(UO2)(3)(CO3)(6)](6-). Focusing on the structures in solution, we applied for the first time a full solvation treatment to these complexes. We approximated short-range effects by explicit aqua ligands and desc...     »

ISI Document Delivery No.: 608MI Times Cited: 3 Cited Reference Count: 78 Schlosser, Florian Moskaleva, Lyudmila V. Kremleva, Alena Krueger, Sven Roesch, Notker Moskaleva, Lyudmila/D-1889-2012; Kremleva, Alena/K-7309-2012 Bundesministerium fur Wirtschaft und Technologie [02E9450, 02E9693]; Fonds der Chemischen Industrie (Germany) This work was supported by the Bundesministerium fur Wirtschaft und Technologie (grants no. 02E9450, 02E9693) and Fonds der Chemischen Industrie (Germany). 3 Royal soc chemistry Cambridge     «

ISI Document Delivery No.: 608MI Times Cited: 3 Cited Reference Count: 78 Schlosser, Florian Moskaleva, Lyudmila V. Kremleva, Alena Krueger, Sven Roesch, Notker Moskaleva, Lyudmila/D-1889-2012; Kremleva, Alena/K-7309-2012 Bundesministerium fur Wirtschaft und Technologie [02E9450, 02E9693]; Fonds der Chemischen Industrie (Germany) This work was supported by the Bundesministerium fur Wirtschaft und Technologie (grants no. 02E9450, 02E9693) and Fonds der Chemischen Industrie (Germany). 3 Royal so...     »