Magnetic and Superconducting Properties of the Heterogeneous Layered Structures V/Fe0.7V0.3/V/Fe0.7V0.3/Nb and Nb/Ni0.65(0.81)Cu0.35(0.19)

Journal of Experimental and Theoretical Physics - The heterogeneous ferromagnetic–superconducting layered heterostructures V/Fe0.7V0.3/V/Fe0.7V0.3/Nb and Nb/Ni0.65(0.81)Cu0.35(0.19), which...     

Deca(hydroxo)-23-aqua-hexa(lanthanum(III)) iodide octahydrate and deca(hydroxo)-23-aqua-hexa(neodymium(III)) iodide octahydrate: Syntheses and structures

New hexanuclear complexes of lanthanum and neodymium iodides, [La₆(H₂O)₂₃(OH)₁₀]I₈ · 8H₂O (I) and [Nd₆(H₂O)₂₃(OH)₁₀]I₈ · 8H₂O (II), are synthesized and studied by X-ray diffraction analysis. The isostructural crystals of complexes I and II are orthorhombic: a = 13.197(4) Å, b = 15.152(3) Å, c = 15.302(4) Å and a = 13.060(4) Å, b = 14.967(5) Å, c = 15.098(4) Å, respectively; Z = 2, space group Pnnm. The lanthanum (neodymium) atoms coordinate the aqua and hydroxo ligands and enter the composition of the Ln₆ -containing complex cations. The coordination polyhedron (ignoring the central oxygen atom) of each atom of the complexing agent is somewhat distorted square antiprism with the aqua and hydroxo ligands being in the vertices. Four bridging ligands link this atom of the complexing agent with the four adjacent atoms.     

Reactions of copper(II) polyfluorinated Β-diketonates and Β-ketoesterates with hydrazines

It has been shown that pyrazoles (hydroxypyrazoles) are formed upon reaction of fluorine-containing copper -diketonates (-ketoesterates) with hydrazines and their hydrochlorides. A preparative method has been developed for the synthesis of fluorinated pyrazoles and hydroxypyrazoles via treatment of fluorine-containing -diketonate and -ketoesterate copper compounds with hydrazines. The molecular structure of 1-phenyl-3-octafluorobutyl-5-hydroxypyrazole has been established based on x-ray structural analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 640–645, March, 1990.     

Interrelation between the real structure and the magnetic properties of Fe1−xS1−ySey solid solutions

The paper investigates the influence of the concentration and the mode of distribution of cation vacancies in the metal sublattice on the magnetic properties of iron sulfide and quasibinary Fe_1–xS_1–ySe_y solid solutions. A correlation is established between the distinctive features of changes in the real structure and magnetic transformations. A schematic diagram is constructed for the structural and magnetic states of Fe_1–xS and Fe_1–xS_1–ySe_y.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 71–75, March, 1982.     

Investigation of Hydrogen Evolution Reaction on (TiCr1.8)xV100 – x Alloys via Impedance Spectroscopy Method

Russian Journal of Electrochemistry - The behavior of the (TiCr1.8)xV100 – x intermetallic system in the reaction of hydrogen evolution in 1 M KOH solution has been studied...     

Magnetic patterns and flux pinning in Pd0.99Fe0.01-Nb hybrid structures

The magnetic properties of hybrid thin-film Pd_0.99Fe_0.01-Nb structures are studied by a magneto-optical technique. It is shown that, below 14 K, the samples exhibit the ferromagnetic ordering corresponding to the formation of weakly coupled ferromagnetic nanoclusters. In the clusters, the effective spin polarization of Fe ions is about 4μ_B, corresponding to that in the bulk Pd₃Fe alloy. The proximity of the ferromagnetic layer does not suppress the superconductivity in niobium. It does not affect the superconducting transition temperature but leads to an enhanced pinning and results in an increase in the critical current by about 30%. This behavior agrees well with the existence of the nanocluster structure in the ferromagnetic film.     

Synthesis and structure of complex compounds of lanthanum,europium, and scandium iodides with antipyrine

Synthesis and X-ray single-crystal diffraction study of antipyrine complexes of lanthanum, europium, and scandium iodides were performed. In all compounds, the inner coordination sphere of the complex cation is an octahedron formed by antipyrine molecules coordinated through the oxygen atoms of the C=O groups.     

Direct Observation of Vortex and Meissner Domains in a Ferromagnetic Superconductor EuFe2(As0.79P0.21)2 Single Crystal

JETP Letters - A spontaneous vortex structure in magnetic domains (vortex domains) has been visualized by the decoration technique near the ferromagnetic transition temperature (TC = 18 K) in a...     

Cyclization of fluoroalkyl-containing 1,3-dicarbonyl compounds with ethylenediamine hydroperchlorate to 1,4-diazepines

2,3-Dihydro-1H-1,4-diazepines and 1,2,3,4-tetrahydro-1,4-diazepin-5-ones were obtained by direct condensation of fluorine-containing 1,3-diketones and 1,3-keto ethers, respectively, with ethylenediamine monohydroperchlorate. The structure of the compounds was confirmed by¹H NMR, mass spectrometry and molecular weight determination.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 890–896, April, 1991.