Speciation of uranyl complexes in ionic liquids by optical spectroscopy

Peter Nockemann, K. Servaes, R. Van Deun, K. Van Hecke, L. Van Meervelt, K. Binnemans, C. Gorller-Walrand

Research output: Contribution to journalArticlepeer-review

100 Citations (Scopus)


Uranyl complexes dissolved in room-temperature ionic liquids have diagnostic absorption and emission spectra which reflect the molecular symmetry and geometry. In particular, the characteristic vibrational fine structure of the absorption spectra allows identification of the molecular symmetry of a uranyl complex. The concept of speciation of. uranyl complexes is illustrated for the hydrated uranyl ion, the tetrachloro complex [UO2Cl4](2-), the trinitrato complex [UO2(NO3)(3)](-), the triacetato complex [UO2(CH3COO)(3)](-) and the crown ether complex [UO2(18-crown-6)](2+) in imidazolium and pyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquids. The competition between 18- crown-6 and small inorganic ligands for coordination to the uranyl ion was investigated. The crystal structures of the hydrolysis product [(UO2)(2)(mu(2)-OH)(2)(H2O)(6)] [UO2Br4](18-crown-6)(4) and imidazolium salt [C(6)mim](2)[UO2Br4] are described.
Original languageEnglish
Pages (from-to)11335-11344
Number of pages10
JournalInorganic Chemistry
Issue number26
Publication statusPublished - 24 Dec 2007

ASJC Scopus subject areas

  • Inorganic Chemistry


Dive into the research topics of 'Speciation of uranyl complexes in ionic liquids by optical spectroscopy'. Together they form a unique fingerprint.

Cite this