22541-17-9Relevant academic research and scientific papers
On the ternary system samarium-nitrogen-oxygen and the question of lower oxides of samarium
Felmlee,Eyring
, p. 660 - 666 (1968)
The ternary compounds SmN1-xOx (0 1-xOx, which has the N
Order—Disorder transformation and its effect on the properties of (Lanthanide)2Zr1.5Hf0.5O7 functional nanoceramics
Rejith,Thomas, Jijimon K.,Solomon, Sam
, p. 1 - 11 (2019/03/14)
Order disorder transformations and its effect on the structural, optical and ionic transport properties of the cubic pyrochlore – defect fluorite structures are the prime focus of this study. Nanoceramics of Ln2Zr1.5Hf0.5O7 (Ln = Pr, Nd, Sm, Gd, Dy and Er) are prepared through the modified combustion technique. X – ray diffraction analysis and electron microscopic studies show the cubic nano crystallite nature of the materials. Vibrational studies reveal the pyrochlore–fluorite phase transformation in the series. Highly dense bulk ceramics are prepared from the nano particles at relatively low temperatures. The gradual replacement of Ln3+ ions in Ln2Zr1.5Hf0.5O7 changes the pyrochlores (Ln = Pr-Sm) to defect fluorite (Ln = Er) through the weakly ordered defect fluorites (Ln = Gd and Dy). Impedance spectroscopic analysis carried on the bulk ceramics shows the influence of phase transformation on the oxide ion conduction of bulk materials. The peak oxide ion conduction is observed for the Ln = Dy ceramic, which is at the pyrochlore fluorite phase boundary.
Effect of the 18-crown-6 and benzo-18-crown-6 on the solvent extraction and separation of lanthanide(III) ions with 8-hydroxyquinoline
Atanassova
, p. 1304 - 1311 (2008/10/09)
The synergistic solvent extraction of 13 lanthanides with mixtures of 8-hydroxyquinoline (HQ) and the crown ethers (S) 18-crown-6 (18C6) or benzo-18-crown-6 (B18C6) in 1,2-dichloroethane has been studied. The composition of the extracted species has been
Synthesis of Samarium, Europium, and Ytterbium Acetylides
Bochkarev, M. N.,Fedorova, E. A.,Glushkova, N. V.,Protchenko, A. V.,Druzhkov, O. N.,Khorshev, S. Ya.
, p. 1465 - 1467 (2008/10/08)
Ethynyl complexes of samarium, europium, and ytterbium were obtained by the reaction of naphthalides of these metals with acetylene in tetrahydrofuran. The complexes were isolated as dark-colored pyrophoric powders. Magnetic data indicate that Sm(II) is oxidized into Sm(III) completely in the course of the reaction, Yb(II) is partially converted into Yb(III), whereas europium retains its initial bivalent state. Hydrolysis of thecompounds obtained yields acetylene, ethylene, ethane, and hydrogen, wh ich indicates the presence of the Ln-C.tplbnd.C-Ln acetylide and the Ln-H hydride groups (Ln=Sm, Eu, and Yb).
Thermodynamic and Electrochemical Behaviour of Lanthanide Cryptates in N,N-Dimethylformamide
Marolleau, Isabelle,Gisselbrecht, Jean-Paul,Gross, Maurice,Arnaud-Neu, Francoise,Schwing-Weill, Marie-Jose
, p. 367 - 370 (2007/10/02)
The stability of 222 (L1), 221 (L2), 211 (L3) cryptates of samarium(III), europium(III), and ytterbium(III) and the corresponding complexes with the related monocycle, 22 (L4) have been determined in N,N-dimethylformamide by potentiometry using a competitive method with auxiliary alkali cations.Their electrochemical behaviour has also been investigated in the same solvent by polarography and cyclic voltammetry.The results clearly show the low stability of the trivalent cryptates.The electrochemical study of Ln(3+) ions with increasing amounts of ligand shows two different behaviours: (i) with L3, Ln(3+) ions are complexed as shown by the decrease of the reduction waves of Ln(3+) but no stabilization of Ln(2+) is observed; (ii) with L1, L2, and L4 the height of the reduction wave of Ln(3+) is not affected by the ligand concentration and the reduction occurs according to the scheme: Ln(3+) + e(1-) Ln(2+) + L -> (2+).The differences δ between the redox potentials of the free and the complexed lanthanide(III) cations show an important stabilization of the divalent cryptates.Their stability constants have been calculated from the values of δ and the stability constants of trivalent complexes.While no particular ligand or cation selectivity is observed for the trivalent cryptates, this is not so for the reduced lanthanides which form the strongest complexes with L1.The results are interpreted by size and solvation considerations.
Acid Solvolysis Kinetics of Lanthanide Porphyrins
Haye, Shirleyanne,Hambright, Peter
, p. 666 - 668 (2007/10/02)
The kinetics of the acid solvolysis reactions of twelve water-soluble lanthanide tetrakis(N-methyl-4-pyridyl)porphyrins (Ln-P) follow rate = k1+>2/ (k-1/k2) + +>> at 25 deg C, I = 0.8M (LiNO3/HNO3) indicating that two protons are required for solvolysis, and since log (k1k2/k-1) = 45.0R0 - 39.4 (R0 is the ionic radius in Angstroem), a 0.1 Angstroem change in radius has a 32000 fold rate effect.
