Complexation of the Carbonate, Nitrate, and Acetate Anions with the Uranyl Dication: Density Functional Studies with Relativistic Effective Core Potentials

Journal Article · Thu Dec 22 04:00:00 EST 2005 · Journal of Physical Chemistry A: Molecules, Spectroscopy, Kinetics, Environment, amp General Theory

DOI:https://doi.org/10.1021/jp0541462· OSTI ID:876960

De Jong, Wibe A; Apra, Edoardo; Windus, Theresa L; Nichols, Jeffrey A; Harrison, Robert J; Gutowski, Keith E; Dixon, David A

The structures and vibrational frequencies of uranyl carbonates, [UO?(CO?)n](?- ??) and [(UO?)?(CO?)?]??, uranyl nitrates, [UO? (NO?)n](?-?), and uranyl acetates, [UO?(CH?COO)n](?-?) (n = 1,2,3) have been calculated by using local density functional theory (LDFT). Only bidentate ligand coordination modes to the uranyl dication have been modeled. The calculated structures and frequencies are compared to available experimental data, including IR, Raman, X-ray diffraction, and EXAFS solution and crystal structure data. The energetics of ligand binding have been calculated using the B3LYP hybrid functional. In general, the structural and vibrational results at the LDFT level are in good agreement with experimental results and provide realistic pictures of solution phase and solid state behavior. For the [UO? (CO?)?]?? anion, calculations suggest that complexity in the CO??? stretching signature upon complexation is due to the formation of C=O and C-O domains, the latter of which can split by as much as 300 cm??. Assessment of the binding energies indicate that the [UO? (CO?)?]?? anion is more stable than the [UO?(CO?)?]?? anion due to the accumulation of excess charge, whereas the tri-ligand species are the most stable in the nitrate and acetate anions.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 876960
• Report Number(s): PNNL-SA-46444; 9598; KP1303000
• Journal Information: Journal of Physical Chemistry A: Molecules, Spectroscopy, Kinetics, Environment, amp General Theory, Journal Name: Journal of Physical Chemistry A: Molecules, Spectroscopy, Kinetics, Environment, amp General Theory Journal Issue: 50 Vol. 109; ISSN 1089-5639; ISSN JPCAFH
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ACETATES
ANIONS
CRYSTAL STRUCTURE
Environmental Molecular Sciences Laboratory
FUNCTIONALS
NITRATES
URANYL CARBONATES
URANYL NITRATES
X-RAY DIFFRACTION