Vibrational Spectroscopy of Anionic Nitrate Complexes of UO₂2+ and Eu³+ Isolated in the Gas Phase

Journal Article · Tue Jan 01 04:00:00 EST 2008 · Physical Chemistry Chemical Physics. PCCP, 10(8):1192-1202

DOI:https://doi.org/10.1039/b715337f· OSTI ID:927275

Groenewold, G S; Oomens, Jos; De Jong, Wibe A; Gresham, Garold L; McIIwain, Michael E; Van Stipdonk, Michael J

Wavelength-selective infrared multiple photon photo-dissociation (IRMPD) was used to generate infrared spectra of anionic nitrate complexes of UO₂²+ and Eu3+ in the mid-infrared region. A pattern of absorptions were observed for both species, including splitting of the antisymmetric O-N-O stretch into high and low frequency components with the magnitude of the splitting consistent with attachment of nitrate to a strong Lewis acid center. The frequencies measured for [UO2(NO3)3]- were within a few cm-1 of those measured in the condensed phase, the best agreement yet achieved for a comparison of IRMPD with condensed phase absorption spectra. In addition, experimentally-determined values were in good general agreement with those predicted by DFT calculations, especially for the antisymmetric UO₂ stretch. The spectrum from the [UO₂ (NO₃)₃]- was compared with that of [Eu(NO3)4]-, which showed that nitrate was bound more strongly to the Eu3+ metal center, consistent with its higher charge. The spectrum of a unique uranyl-oxo species having an elemental composition [UO9N₃]- was also acquired, for which calculations suggested a [UO₂(NO₃)₂(O)]- structure.

• 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: 927275
• Report Number(s): PNNL-SA-57453; 9598
• Journal Information: Physical Chemistry Chemical Physics. PCCP, 10(8):1192-1202, Journal Name: Physical Chemistry Chemical Physics. PCCP, 10(8):1192-1202 Journal Issue: 8 Vol. 10
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ABSORPTION SPECTRA
Environmental Molecular Sciences Laboratory
INFRARED SPECTRA
LEWIS ACIDS
NITRATES
PHOTONS
SPECTROSCOPY