Crystal structure of SrFe(<Emphasis Type="Italic">EDTA</Emphasis>)Cl · 5H<Subscript>2</Subscript>O

The crystal structure of the SrFe(Edta)Cl · 5H₂O (I) complex is determined. The crystals are monoclinic, a = 7.530(4) Å, b = 10.575(3) Å, c = 23.308(10) Å, β = 95.75(4)°, Z = 4, and space group P2₁/c. The structural units of I are infinite ribbons of the molecular type that are formed by tetranuclear fragments. A tetranuclear fragment involves the centrosymmetric positively charged dimer group [Sr(H₂O)₄Cl] ₂ ²⁺ at the center and the [Fe(Edta)(H₂O)]_? anionic complexes, which compensate for the positive charge of the dimer group, at the periphery. These constituents are bound via bridging oxygen atoms of the Edta ligands. The coordination number of the Sr atom is nine. The Sr-O bond lengths lie in the range between 2.552 and 2.766 Å, the Sr-Cl bond length is 3.216(3) Å, and the Sr?Sr distance is 4.371(1) Å. The parameters of the [Fe(Edta)(H₂O)]^? group are within the range of values observed in such complexes: Fe-O, 1.996–2.086(3) Å; Fe-O(w), 2.110(4) Å; and Fe-N, 2.289(4) and 2.327(4) Å. Separate ribbons are linked by hydrogen bonds involving all H₂O molecules and terminal oxygen atoms of the Edta ligand.     

Synthesis and physicochemical investigation of mixed alkali-metal cation hexafluorosilicates

The title compounds of MMSiF₆ (M, M=Li, Na, K, Rb, Cs) and Li_0.5Na_1.5SiF₆ composition have been synthesized. Their crystallographic, x-ray, and IR spectral properties were studied. The greatest distortion of the C_3v symmetry of the hexafluorosilicate ion was observed in Li_0.5Na_1.5SiF₆ crystal.Institute of Chemistry, Far Eastern Branch, Russian Academy of Sciences, 690022 Vladivostok. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 263–272, February, 1992.     

Ionic mobility, ionic transport, and charge transfer mechanism in solid solutions (1 ? x )PbF2- x MF n by the NMR and impedance spectroscopy data

The internal mobility and ionic conduction of solid solutions in systems PbF₂-MF₂ and PbF₂-MF₃ are studied by the NMR (¹⁹F, ²⁷Al, ²⁰⁷Pb) and impedance spectroscopy methods. Factors that define the form of ionic movements and their energy characteristics in the temperature region 150 to 550 K are considered and analyzed. Temperature shifts of the frequency range that defines the ionic conduction of solid solutions are discovered on the basis of impedance spectroscopy data and explained. It is established that the high ionic conductance in lead difluoride doped with fluorides of metals of Groups II and III is caused by the diffusion of fluoride ions. The large values of specific conductance (10⁻⁴ to 10⁻³ S cm⁻¹) at a relatively low activation energy (less than 0.6 eV) allow one to consider the solid solutions studied in the role of a basis for the obtaining of new fluoride materials with high ionic conductance. Original Russian Text ? V.Ya. Kavun, A.B. Slobodyuk, S.L. Sinebryukhov, E.V. Tararako, V.K. Goncharuk, S.V. Gnedenkov, V.I. Sergienko, 2007, published in Elektrokhimiya, 2007, Vol. 43, No. 6, pp. 643–656. Based on the report delivered at the 8th International Meeting on Fundamental Problems of Solid-State Ionics, Chernogolovka (Russia), 2006.     

Synthesis and crystal structure of the molecules of 1-(2-benzothiazolyl)-3,5-dimethylpyrazole C12H11N3S and dioxodichloro[1-(2-benzothiazolyl)-3,5-dimethylpyrazole]molybdenum(VI) [MoO2(C12H11N3S)Cl2]

N. S. Kurnakov Institute of General and Inorganic Chemistry, Academy of Sciences of the USSR. Scientific-Research Institute of, Physical and Organic Chemistry, Rostov State University. Voroshilovgrad Mechanical Engineering Institute. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 5, pp. 45–53, September–October, 1990.     

Synthesis and Structure of (4-Acetyl-3-hydroxyphenoxy)tetraphenylantimony

Pentaphenylantimony was reacted with 4-acetyl-1,3-dihydroxybenzene in toluene at elevated temperature to obtain (4-acetyl-3-hydroxyphenoxy)tetraphenylantimony in 93% yield. According to X-ray diffraction data, the antimony atom in (4-acetyl-3-hydroxy-phenoxy)tetraphenylantimony has a distorted trigonal-bipyramidal configuration. The Sb-O and Sb-C distances are 2.237(1) and 2.112(1), 2.114(2), 2.118(2), 2.170(2) Å, respectively, and the CSbO angle is 177.86(5)°.     

Crystal Structures of LiCsTiF6 and Cs2TiF6 and Internal Mobility of Complex Anions

Single crystals of LiCsTiF₆(I) and Cs₂TiF₆(II) are characterized by X-ray diffraction analysis (DAR-UMBk and SMART 1000 CCD diffractometers, MoK radiation, graphite monochromator; anisotropic least squares refinement to R = 0.038 and R _w = 0.046 (I) and R ₁ = 0.017 and wR ₂ = 0.046 (II)). Packing modes of structural units in the crystals are considered. Types of internal motions of complex TiF₆ ^2– ions are established, and their activation energies in the crystals of LiCsTiF₆ and Cs₂TiF₆ are estimated in the temperature range 200–500 K.     

Synthesis,properties, and crystal structure of {<Emphasis Type="Italic">N</Emphasis>-(2-hydroxyethyl)ethylenediaminetriacetato}hydroxogermanium(IV) sesquihydrate [Ge(OH)(HHedtra)] · 1.5H<Subscript>2</Subscript>O

The previously unknown germanium(IV) complex with N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetic acid (H₄Hedtra) was synthesized. The complex was characterized by elemental analysis, X-ray powder diffraction, thermogravimetry, and IR spectroscopy. The structure of the [[Ge(OH)(HHedtra)] · 1.5H₂O (complex I) was established by X-ray diffraction. The crystals are triclinic, a = 6.7380(13) Å, b = 14.643(2) Å, c = 15.4360(10) Å, α= 104.452(6)°, β = 100.293(6)°, γ = 96.643(5)°, V = 1430.4(4) ų, Z = 2, space group \(P\bar 1\), R = 0.0356 based on 6108 reflections with I > 2σ(I). In each crystallographically independent [Ge(OH)(HHedtra)] complex molecule, the Ge atom is coordinated by two nitrogen atoms and three oxygen atoms of three acetate branches of the pentadentate chelating ligand HHedtra^3? (avg. Ge-N, 2.082(2) Å; Ge-O, 1.890(2) Å). The octahedral coordination of the metal atom involves also the O atom of the hydroxo ligand (avg. Ge-OH, 1.766(2) Å). In the crystal structure, the complex molecules and crystal-water molecules are linked to each other by a hydrogen-bond network.     

Crystal and molecular structures of the copper dichloride complex with 1-isopropenylimidazole

Crystal and molecular structures of the [CuL₂Cl₂] complex (L is 1-isopropenylimidazole) (I) are determined (R = 0.038, (wR ₂ = 0.092 for 2026 reflections with F _o ≥ 4σ(F _o); R ₁ = 0.123, wR ₂ = 0.117 for all reflections)) and compared with the structure of the known cobalt complex of analogous composition [CoL₂Cl₂] (II). Unlike complex II with the usual tetrahedral environment of the cobalt atom, the structure of the coordination polyhedron of the copper atom in compound I is intermediate between tetrahedron and square (the average dihedral angle between the ClCuN planes is 35.9°, and the ClCuCl (147.5°) and NCuN (163.1°) angles are much larger than the ClCuN angle of 90.1°–93.1°). The Cu-N (1.975(3), 1.959(3) Å) and Cu-Cl bonds (2.291(1), 2.278(1) Å) in complex I are typical of the copper(II) compounds. Different spatial structures of the 1-alkenylimidazole cycles in complexes I and II are found. Different short intermolecular contacts in crystals of compounds I (Cu…Cl, Cu…H) and II (Cl…C) result in the formation of chains with different mutual arrangements of molecules of the complexes.