Raman spectrometric studies of Cation-Cation complexes of pentavalent actinides in aqueous perchlorate solutions

Journal Article · Mon Mar 01 04:00:00 EST 1982 · Inorg. Chem.; (United States)

DOI:https://doi.org/10.1021/ic00133a055· OSTI ID:5582790

Guillaume, B; Begun, G M; Hahn, R L

Complexation of actinyl(V) ions in aqueous solution has been studied by Raman spectral and spectrophotometric measurements. Addition of UO/sub 2//sup 2 +/ to aqueous perchlorate solutions of NpO/sub 2//sup +/ or AmO/sub 2//sup +/ was found to result in the formation of distinct new species with lowered values of ..nu../sub 1/, the symmetrical stretching frequency of the actinyl ion. The Np(V)-U(VI) complexation constant was determined by Raman spectroscopy to be K/GAMMA = 2.5 +- 0.5 at U(VI) concentrations below 1 M. For the weaker Am(V)-U(VI) complex, the value of K/GAMMA was approximately 0.3. These complexation constants determined by Raman spectroscopy agreed well with the results of spectrophotometric ultraviolet-visible observations. For concentrated NpO/sub 2//sup +/ solutions, the Raman data gave evidence for a new form of cation-cation complex, that formed by the self-association of pentavalent actinyl ions. Above 0.2 M concentration, a dimer is formed with K/sub 2//GAMMA = 0.82 +- 0.05, while at higher neptunyl(V) concentration, higher polymers are formed. The effects of a number of other complexing cations upon the ..nu../sub 1/ spectral band of NpO/sub 2//sup +/ were also observed.

• Research Organization: Oak Ridge National Lab., TN
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5582790
• Journal Information: Inorg. Chem.; (United States), Journal Name: Inorg. Chem.; (United States) Vol. 21:3; ISSN INOCA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400702* -- Radiochemistry & Nuclear Chemistry-- Properties of Radioactive Materials
ABSORPTION SPECTRA
ACTINIDE COMPLEXES
ACTINIDE COMPOUNDS
AMERICIUM COMPLEXES
AMERICIUM COMPOUNDS
AMERICIUM OXIDES
AQUEOUS SOLUTIONS
CATIONS
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
CHLORINE COMPOUNDS
COMPLEXES
DATA
DIMERS
DISPERSIONS
EXPERIMENTAL DATA
HALOGEN COMPOUNDS
INFORMATION
IONS
KINETICS
MIXTURES
NEPTUNIUM COMPLEXES
NEPTUNIUM COMPOUNDS
NEPTUNYL COMPOUNDS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PERCHLORATES
POLYMERS
RAMAN SPECTRA
REACTION KINETICS
SOLUTIONS
SPECTRA
TRANSPLUTONIUM COMPOUNDS
TRANSURANIUM COMPLEXES
TRANSURANIUM COMPOUNDS
URANIUM COMPLEXES
URANIUM COMPOUNDS
URANYL COMPOUNDS
VALENCE
YIELDS