No abstract available

No abstract available

[en] The absorption spectra of uranium(+3) in 2 M HC10₄, of uranium(+3) chloro-complexes in anhydrous methyl alcohol and dimethylformamide, and of uranium(+3) thiocyanato-complexes in anhydrous methyl alcohol, were recorded in the range 4000 to 50,000 cm^-1. An intensity analysis of f-f transitions of the uranium(+3) spectra in 2 M HC10₄ and anhydrous methyl alcohol, has been made and is discussed with respect to the energy level assignment. Calculations of the 'free ion' energy levels, were carried out in order to determine which states of the configuration 5f³ are most sensitive to changes in the energy level parameters. (author)

No abstract available

No abstract available

[en] A possibility of quantitative mathematical description of simultaneous influence of induction and steric effects of the substituents at nitrogen atom in amine on the extraction capacity (the extraction constant K) has been considered. The coefficients of the equations have been determined for a number of extraction systems including HNO₃, Pu(NO₃)₄, Np(NO₃)₄, HCl, and HBr. The Esub(s)sup(*) parameters characterizing steric effects of the substituents have been specified. The quantitative consideration of the steric factors, performed for the first time, has shown that a decrease in extraction capacity of secondary amines (as compared with salts of tertiary amines) cannot be explained by a decrease in induction effects of substituents only (since such a change should be compensated by a contrary effect of decreasing steric hyndrances) but may be due to the influence of other factors (hydrophility or self-solvation of salts, etc.) which must be more thoroughly studied

[en] The conditions of the formation have been studied and the compositions have been determined for di-n-butylphosphates of zirconium, thorium, and tetravalent plutonium separated from the solutions of di-n-butylphosphoric acid (DBP,HA) in a mixture of 10 vol.% of tri-n-butylphosphate (TBP) with organic diluents (benzene, carbon tetrachloride, gasoline). It is shown that irrespective of the ratio of HA: zirconium (within the range of 0.66-4.2) the precipitates of the Zr(NO₃)₂A₂ composition are separated in the solutions. Plutonium and thorium form the precipitates of the Pu(NO₃)₂A₂ and ThA₄ composition only from the solutions with gasoline. Chemical analysis and cryoscopic study of the precipitates have been made. It is shown that the polymerization degree of the plutonium compound is about 11. Infrared spectroscopic study of the precipitates has been conducted, and possible structures of the obtained compounds of DBP with metals are

[en] A valence-bond approach using bidirectional orbitals is employed in a discussion of the uranium bonding in CrUS₃. The unpaired outermost-bound uranium electron density recently discovered in this new semiconducting material is identified with a dsub(z²) uranium orbital extending through and beyond the uranium valence electrons. The f character employed in bond formation by uranium is estimated to be 20 to 30%. (author)

No abstract available

[en] The oxine adduct of Th(IV) oxinate and divalent copper, zinc, and cobalt oxinates reacted with trichloroacetic acid to produce mixed ligand complexes in which the oxinate is bidentate in the Th(IV) and Cu(II) complexes and monodentate, coordinated as a zwitterion through its phenolate oxygen, in the Zn(II) and Co(II) complexes. The reaction of Co(II) oxinate with picric acid or 2,4 dinitrophenol resulted in the formation of a charge transfer type of complexes in which the ratio of the cobalt oxinate to nitrophenol is 2:1. Analytical and spectral evidence are in accordance with the suggested structures. (author)