[Na(12-Krone-4)2]2[Ni(Se4)2] · DMF; Synthese,Kristallstruktur und magnetisches Verhalten

[Na(12-Crown-4)₂]₂[Ni(Se₄)₂] · DMF; Synthesis, Crystal Structure, and Magnetic Behaviour The title compound has been prepared from NiCl₂ and sodium polyselenide in dimethylformamide solution in the presence of 12-crown-4, forming black crystal needles. They were characterized by an X-ray structure determination, by FIR spectroscopy as well as by the magnetic behaviour. [Na(12-crown-4)₂]₂[Ni(Se₄)₂] · DMF crystallizes monoclinically in the space group P2₁, 3650 observed unique reflections, R = 0.046. Lattice dimensions at ?80°C: a = 1020.3(2); b = 1889.5(2); c = 1498.7(3) pm; β = 108.29(1)°. The compound has an ionic structure, in which the sodium atoms of the [Na(12-crown-4)₂]⁺ cations are coordinated by the oxygen atoms of the crown ether molecules in an antiprismatic fashion. The nickel atom of the anion [Ni(Se₄)₂]^2? is surrounded by four selenium atoms of the tetraselenide chelates in an almost planar environment. The DMF molecules are inserted in the lattice without a bonding interaction. The magnetic susceptibility observed in the temperature interval 4.2 to 330K can be interpreted by means of a ³E ground term and D₂ as local symmetry, which was established by X-ray crystallography.     

Synthese und Kristallstrukturen der Polyselenidokomplexe (PPh4)6[M(Se4)2]2[WSe4] · DMF mit M = Zink und Quecksilber

Syntheses and Crystal Structures of the Polyselenido Complexes (PPh₄)₆[M(Se₄)₂]₂[WSe₄] · DMF with M = Zinc and Mercury The title compounds have been prepared by the reactions of the acetates of zinc and mercury, respectively, with excess (PPh₄)₂ WSe₄ in boiling dimethylformamide, forming black-red single crystals. According to the X-ray structure determinations both compounds crystallize isotypically in the space group 12/a with four formula units per unit cell. (PPh₄)₆[Zn(Se₄)₂]₂[WSe₄] · DMF: a = 2888.1(6), b = 1740.3(2), c = 2893.9(4) pm, β = 90.47(1)°. 3230 observed unique reflections, R = 0.009. (PPh₄)₆[Hg(Se₄)₂]₂[WSe₄] · DMF: a = 2891.8(5), b = 1738.0(4), c = 2920.1(5) pm, β = 90.29(2)°. 2978 observed unique reflections, R = 0.115%. The compounds consist of PPh₄⁺ ions, spirocyclic octaseleno metallates [M(Se₄)₂]^2?, tetrahedral WSe₄²-ions, and disordered DMF Molecules.     

Chloro- und Polyselenoselenate(II) Darstellung,Struktur und Eigenschaften von [Ph3(C2H4OH)P]2[SeCl4] · MeCN, [Ph4P]2[Se2Cl6] und [Ph4P]2[Se(Se5)2]

Chloro- and Polyselenoselenates(II): Synthesis, Structure, and Properties of [Ph₃(C₂H₄OH)P]₂[SeCl₄] · MeCN, [Ph₄P]₂[Se₂Cl₆], and [Ph₄P]₂[Se(Se₅)₂] By symproportionation of elemental selenium and SeCl₄ in polar protic solvents the novel chloroselenates(+II), [SeCl₄]^2? and [Se₂Cl₆]^2?, could be stabilized; they were crystallized with voluminous organic cations. They were characterized from complete X-ray structure analysis. Yellow-orange [Ph₃(C₂H₄OH)P]₂[SeCl₄] · MeCN (space group P1 , a = 10.535(4), b = 12.204(5), c = 16.845(6) Å, α = 77.09(3)°, β = 76.40(3)°, γ = 82.75(3)° at 140 K) contains in its crystal structure monomeric [SeCl₄]^2? anions with square-planar coordination of Se(+II). The mean Se? Cl bond length is 2.441 Å. In yellow [Ph₄P]₂[Se₂Cl₆] (space group P1 , a = 10.269(3), b = 10.836(4), c = 10.872(3) Å, α = 80.26(3)°, β = 79.84(2)°, γ = 72.21(3)° at 140 K) a dinuclear centrosymmetric [Se₂Cl₆]^2? anion, also with square-planar coordinated Se(+II), is observed. The average terminal and bridging Se? Cl bond distances are 2.273 and 2.680 Å, respectively. From redox reactions of elemental Se with boranate/thiolate in ethanol/DMF the bis(pentaselenido)selenate(+II) anion [Se(Se₅)₂]^2? was prepared as a novel type of a mixed-valent chalcogenide. In dark-red-brown [Ph₄P]₂[Se(Se₅)₂] (space group P2₁/n, a = 12.748(4), b = 14.659(5), c = 14.036(5) Å, β = 108.53(3)° at 140 K) centrosymmetric molecular [Se(Se₅)₂]^2? anions with square-planar coordination of the central Se(+II) by two bidentate pentaselenide ligands is observed (mean Se? Se bond lengths: 2.658 Å at Se(+II), 2.322 Å in [Se₅]_2?). The resulting six-membered chelate rings with chair conformation are spirocyclically linked through the central Se(+II). The vibrational spectra of the new anions are reported.     

Synthese und Kristallstruktur von [Ba(18-Krone-6)(DMF)4][Cd(Se4)2]

Synthesis and Crystal Structure of [Ba(18-Crown-6)(DMF)₄][Cd(Se₄)₂] The title compound has been prepared by the reaction of a DMF-solution of lithium polyselenide with BaSe₂ and cadmium acetate in the presence of 18-crown-6, forming black crystals. The compound was characterized by IR spectroscopy and by an X-ray structure determination. Space group P2/a, Z = 4, 5392 observed unique reflections, R = 0.048. Lattice dimensions at ?90°C: a = 2021.9(12); b = 1019.8(6); c= 2270.8(14)pm, ß = 106.98(4)°. The structure consists of [Ba(18-crown-6)(DMF)₄]²⁺ ions, in which the barium ions are coordinated by the six oxygen atoms of the crown ether molecule and by four oxygen atoms of the DMF molecules, and of [Cd(Se₄)₂]^2? ions. The cadmium atoms are coordinated by two tetraselenide ions in a chelating fashion.     

Die Kristallstrukturen der Polytelluride [Ca(DMF)6]Te4, [Sr(15-Krone-5)2]Te4 · H2O, {[BaCl(18-Krone-6)(DMF)2]2[BaCl(18-Krone-6)(DMF) (H2O)]2(Te4)2} und [Ph3PNPPh3]2Te5 · 2 DMF

Crystal Structures of the Polytellurides [Ca(DMF)₆]Te₄, [Sr(15-Crown-5)₂]Te₄ · H₂O, {[BaCl(18-Crown-6)(DMF)₂]₂[BaCl(18-Crown-6)(DMF) (H₂O)]₂(Te₄)₂}, and [Ph₃PNPPh₃]₂Te₅ · 2 DMF The title compounds were formed by alkalimetal polytelluride solutions in dimethylformamide (DMF) in the presence of the corresponding counter ions as well as in the presence of 15-crown-5 or 18-crown-6. Single crystals were obtained upon using additional diethylether. [Ca(DMF)₆]Te₄: Space group C2/c, Z = 4, 1024 observed unique reflections, R = 0.055. Lattice dimensions at ?70°C: a = 1776.1; b = 813.0 c = 2545.9pm; β = 102.90°. The compound consists of centrosymmetric [Ca(DMF)⁶]²⁺ ions, in which the calcium ions are octahedrally coordinated by the six oxygen atoms of the DMF molecules, and chain-like Te [Sr)15-crown-5)₂]Te₄ · H₂O: Space group C2/c, Z = 4, 3322 observed unique reflections, R = 0.058. Lattice dimensions at ?70°C: a = 1450.5; b = 1407.3; c = 1660.9 pm; β = 110.22°. The compounds forms centrosymmetric cations [Sr(15-crown-5) ₂]²⁺, in which the Sr²⁺ ion is sandwich-like surrounded by the ten oxygen atoms of the crown ether molecules, and chain-like Te₄^2? ions, which are associated in the lattice forming polymeric chains. {[BaCl(18-crown-6)(DMF) ₂]₂[BaCl(18-crown-6)(DMF)· (H₂O)] ₂(Te₄)₂}: Space group P1 , Z = 1, 3189 observed unique reflections, R = 0.054. Lattice dimensions at 19°C: a = 986.1; b = 1052.8; c = 2696.4 pm; α = 89.34°; β = 88.68°; γ = 89.56°. The compound consists of chain-like Te ions without symmetry and of the two somewhat different cations [BaCl(18-crown-6)(DMF) ₂]₂²⁺, in which the Ba²⁺ ions dimerize via centroysmmetric rings. Along with the six oxygen atoms of the crown ether molecules and the oxygen atoms of the DMF molecules, the oxygen atoms of the DMF and water molecule, respectively, the Ba⁺ ions achieve coordination number ten. [Ph₃PNPPh₃]₂Te₅ · 2DMF: Space group Pc, Z = 2, 5971 observed unique reflections, R = 0.058. Lattice dimensions at 20°C: a = 20°C: a = 1085.2; b = 1287.0; c = 2715.9 pm; β = 90.19°. The compounds consists of [Ph₃PNPPh₃]₊ ions, chain-like Te₅^2? ions, and incorporate DME molecules without bonding interaction. The ₅^2? ions are associate via polymeric chains in which left- and right handed individuals are alternating.     

Synthese und Kristallstruktur von [Na(15-Krone-5)]4[Cd4Te12] · 8 DMF

Synthesis and Crystal Structure of [Na(15-Crown-5)]₄[Cd₄Te₁₂] · 8 DMF The title compound has been prepared by reaction of Na₂Te₃ with cadmium acetate in DMF solution in the presence of 15-crown-5, forming black crystal needles, which were characterized by an X-ray structure determination. Space group P2₁/n, Z = 2, 5 716 observed unique reflections, R = 0.038. Lattice dimensions at ?50°C: a = 1 622.9, b = 2 038.2, c = 1 739.8 pm, β = 92.26°. The compound has an ionic structure. The cations [Na(15-crown-5)(DMF)]⁺ and [Na(15-crown-5) · (DMF)₂]⁺ together with two further DMF molecules form tetrameric units. In the centrosymmetric anions [Cd₄Te₁₂]^4? the cadmium atoms are linked by μ₂-Te^2?-, μ₄-Te₂^2?-, and μ₂-Te₃^2?-units.     

Die Kristallstrukturen der Polyselenide [Cs(18-Krone-6)]2Se5 · DMF, [Rb(222-Crypt)]2Se6, [Ba(15-Krone-5)2]Se6 · DMF und [Na(12-Krone-4)2]2Se7

Crystal Structures of the Polyselenides [Cs(18-Crown-6)]₂Se₅ · DMF, [Rb(222-Crypt)]₂Se₆, [Ba(15-Crown-5)₂]Se₆ · DMF, and [Na(12-Crown-4)₂]Se₇ . The title compounds have been prepared by reactions of the corresponding diselenides with excess selenium in the presence of crown ethers in dimethylformamide solutions, forming black crystals. [Cs(18-Crown-6)]₂Se₅ · DMF: Space group P2₁/m, Z = 2, 2 194 observed unique reflections, R = 0.119. Lattice dimensions at 20°C: a = 1 041.2; b = 1 496.3; c = 1 459.7 pm; β = 100.39°. The compound forms an ionic triple with Cs…Se-contacts between 374 and 381 pm. [Rb(222-Crypt)]₂Se₆: Space group P1 , Z = 2, 7 405 observed unique reflections, R = 0.056. Lattice dimensions at – 70°C: a = 1 106.8; b = 1 460.8; c = 1 718.8 pm; α = 89.22°; β = 86.65°; γ = 71.53°. The compound contains Se₆^2? chains without direct contact with each other. [Ba(15-Crown-5)₂]Se₆ · DMF: Space group P2₁/n, Z = 4, 2 680 observed unique reflections, R = 0.055. Lattice dimensions at – 80°C: a = 1 051.9; b = 1 322.4; c = 2 729.9 pm; β = 100.93°. The compound contains Se₆^2? chains, which are isolated from each other by the cations and the included DMF molecules. [Na(12-Crown-4)₂]₂Se₇: Space group P1 , Z = 2, 7 313 observed unique reflections, R = 0.042. Lattice dimensions at – 70°C: a = 1 260.9; b = 1 433.6; c = 1 462.9 pm; α = 80.27°; β = 78.60°; γ = 69.34°. The compound contains Se₇^2? chains without direct contacts with each other.     

Temperature Influence on the Formation of Selenidoantimonates: Solvothermal Syntheses,Crystal Structures and Thermal Properties of [Ni(dien)2]2Sb2Se6, [Mn(dien)2]2(SbSe4)(Cl), [Co(dien)2]2(SbSe4)(Br), and [Co(dien)2]3(SbSe4)2

New selenidoantimonats [Ni(dien)₂]₂Sb₂Se₆ ( 1 ), [Mn(dien)₂]₂(SbSe₄)(Cl) ( 2 ), [Co(dien)₂]₂(SbSe₄)(Br) ( 3 ), and [Co(dien)₂]₃(SbSe₄)₂ ( 4 ) (dien = diethylenetriamine) were solvothermally synthesized in dien solvent at 180 °C. The crystal structure of 1 consists of two octahedral [Ni(dien)₂]²⁺ cations and a mixed‐valent [Sb₂Se₆]^4? anion. The isolated [Sb₂Se₆]^4? anion is formed by a Sb^IIISe₃ trigonal pyramid and a Sb^VSe₄ tetrahedron sharing a common corner. 2 and 3 are composed of octahedral [M(dien)₂]²⁺ cations, tetrahedral [SbSe₄]^3? anions and halide ions forming an extended network through hydrogen‐bonding interactions. In 4 the [Co(1)(dien)₂]²⁺, [Co(2)(dien)₂]²⁺ and [SbSe₄]^3? ions form layered structures via N–H···Se hydrogen bonds. The [Co(3)(dien)₂]²⁺ ion is located between the layers, and interacts with the layers by N–H···Se bonds. The synthesis and solid state structural studies on the title compounds show that the higher reaction temperature is helpful for the formation of selenidoantimonate(V) compounds in the synthesis of selenidoantimonate from the M²⁺/Sb/Se/dien system. 1 – 4 start to decompose at temperature about 210 °C in N₂ atmosphere. They lose dien ligands at a wide temperature range of 210–450 °C with multisteps for 1 – 3 and a single step for 4 .     

Die Kristallstrukturen von (NH4)2[ReCl6], [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN und [ReCl4(18-Krone-6)]

The Crystal Structures of (NH₄)₂[ReCl₆], [ReCl₂(CH₃CN)₄]₂[ReCl₆] · 2CH₃CN and [ReCl₄(18)(Crown-6)] Brown single crystals of (NH₄)₂[ReCl₆] are formed by the reaction of NH₄Cl with ReCl₅ in a suspension of diethylether. [ReCl₂(CH₃CN)₄]₂[ReCl₆] · 2CH₃CN crystallizes as brown crystal plates from a solution of ReCl₅ in acetonitrile. Lustrous green single crystals of [ReCl₄(18-crown-6)] are obtained by the reaction of 18-crown-6 with ReCl₅ in a dichloromethane suspension. All rhenium compounds are characterized by IR spectroscopy and by crystal structure determinations. (NH₄)₂[ReCl₆]: Space group Fm3 m, Z = 4, 75 observed unique reflections, R = 0.01. Lattice constant at ?70°C: a = 989.0(1) pm. The compound crystallizes in the (NH₄)₂[PtCl₆] type, the Re? Cl distance is 235.5(1) pm. [ReCl₂(CH₃CN)₄]₂[ReCl₆] · 2CH₃CN: Space group P1, Z = 1, 2459 observed unique reflections, R = 0.12. Lattice dimensions at ?60°C: a = 859.0(1), b = 974.2(7), c = 1287.3(7) pm, α = 102.69(5)°, b? = 105.24(7)°, γ = 102.25(8)°. The structure consists of two symmetry-independent [ReCl₂(CH₃CN)₄]⁺ ions with trans chlorine atoms, [ReCl₆]^2? ions, and included acetonitrile molecules. In the cations the Re? Cl bond lengths are 233 pm in average, in the anion they are 235 pm in average. [ReCl₄(18-crown-6)]: Space group P2₁/n, Z = 4, 3 633 observed unique reflections, R = 0.06. Lattice dimensions at ?70°C: a = 1040.2(4), b = 1794.7(5), c = 1090.0(5) pm, b? = 108.91(4)°. The compound forms a molecular structure, in which the rhenium atom is octahedrally coordinated by the four chlorine atoms and by two oxygen atoms of the crown ether molecule.     

Benzeneselenolates of Mercury(II). Crystal and Molecular Structures of [Hg(SePh)2] and (Bu4N)[Hg(SePh)3]

The reaction of dibenzenediselenide, (SePh)₂, with mercury in refluxing xylene gives bis(benzeneselenolato)mercury(II), [Hg(SePh)₂], in a good yield. (ⁿBu₄N)[Hg(SePh)₃] is obtained by the reaction of [Hg(SePh)₂] with a solution of [SePh]^– and (ⁿBu₄N)Br in ethanol. The solid state structures of both compounds have been determined by X-ray diffraction. The mercury atom in [Hg(SePh)₂] (space group C2, a = 7.428(2), b = 5.670(1), c = 14.796(4) Å, β = 103.60(1)°) is linearly co-ordinated by two selenium atoms (Hg–Se = 2.471(2) Å, Se–Hg–Se = 178.0(3)°). Additional weak interactions between the metal and selenium atoms of neighbouring molecules (Hg…Se = 3.4–3.6 Å) associate the [Hg(SePh)₂] units to layers. The crystal structure of (ⁿBu₄N)[Hg(SePh)₃] (space group P2₁/c, a = 9.741(1), b = 17.334(1), c = 21.785(1) Å, β = 95.27(5)°) consists of discrete complex anions and (ⁿBu₄N)⁺ counter ions. The coordination geometry of mercury is distorted trigonal-planar with Hg–Se distances ranging between 2.5 and 2.6 Å.     

Synthesen und Kristallstrukturen der Polytellurido-Komplexe [K(15-Krone-5)2]2[MTe7] mit M = Zn und Hg

Synthesis and Crystal Structures of the Polyellurido Complexes [K(15-Crown-5)₂]₂[MTe₇] with M = Zn and Hg The title compounds were obtained in the presence of 15-crown 5 from solutions of zinc and mercury acetate, respectively, in DMF by addition of a solution of K₂Te₃ in DMF at 0°C (M = Zn) and -50°C (M = Hg). They form black crystal needles with metallic luster. Their crystal structures were determined by X-ray diffraction. The structures of [K(15-crown-5)₂]₂ZnTe₇ and [K(15-crown-5)₂]₂HgTe₇ show two-dimensional disorder as evidence by diffuse scattering. The averaged structures that were determined with the Bragg reflexions correspond to space group Pbcn and have very similar lattice parameters. Nevertheless, the structures differ. [HgTe₇]^2? ions consist of two condensed five membered rings. They are arranged to form strands in the c direction; within of one strand the ions have a definite orientation, but in different strands two different orientations occur randomly. A [ZnTe₇]^2? ion can be thought of consisting of a Zn²⁺ ion, a Te₄^2? ion bonded in a chelate manner and a Te₃^2? ion bonded with one terminal Te atom to the Zn²⁺. The [ZnTe₇]^2? ions are associated to strands in the c direction with two different strand orientations occuring randomly.     

Synthese und Kristallstruktur des Nonaselenids [Sr(15-Krone-5)2]Se9

Synthesis and Crystal Structure of the Nonaselenide [Sr(15-crown-5)₂]Se₉ The title compound was prepared by the reaction of excess selenium with strontium diselenide in DMF in the presence of 15-crown-5. [Sr(15-crown-5)₂]Se₉ forms black crystals, which are soluble in DMF. They were characterized by FIR spectroscopy and by an X-ray structure determination. Space group P2₁/n, Z = 4, 2 381 observed unique reflections, R = 0.073. Lattice dimensions at 19°C: a = 1 228.7, b = 1 893.4, c = 1 575.7 pm, β = 99.15°. The compound consists of [Sr(15-crown-5)₂]²⁺ ions in which the strontium ion is coordinated by the oxygen atoms of the crown ether molecules in a sandwich-like fashion, and of Se₉^2? ions with a chain structure, which has a topolocical resemblance with the bicyclic ion Se.     

Dinuclear Manganese(II) Complexes with Bridging Selenidodiarsenate Anions [As2Se4]4−, [As2Se5]4− and [As2Se6]2−

Solvothermal reaction of [MnCl₂(amine)] (amine = terpy and tren) with elemental As and Se at a 1:1:2 molar ratio in H₂O/tren (10:1) affords the dimanganese(II) complexes [{Mn(terpy)}₂(μ‐As₂Se₄)] ( 1 ) and [{Mn(tren)}₂(μ‐As₂Se₅)] ( 2 ) respectively. The tetradentate [As₂Se₄]^4? bridging ligands in 1 contain a central As–As bond and exhibit approximately C_2h symmetry. Pairs of gauche sited Se atoms participate in five‐membered As₂Se₂Mn chelate rings. In contrast, two AsSe₃ pyramids share a common corner in the [As₂Se₅]^4? ligands of 2 and each coordinates an [Mn(tren)]²⁺ fragment through a single terminal Se atom. Such dinuclear complexes are linked into tetranuclear moieties through weak Se···Mn interactions of length 3.026(3) Å involving one of these terminal Se atoms. At a 1:3:6 molar ratio, solvothermal reaction of [MnCl₂(tren)] with As and Se leads to formation of a second dinuclear complex [{Mn(tren)}₂(μ‐As₂Se₆)₂] ( 3 ), which contains two bridging bidentate [As₂Se₆]^2? ligands. These are cyclic with an As₂Se₄ ring and can be regarded as being derived from [As₂Se₅]^4? anions by formation of two Se‐Se bonds to an additional Se atom.     

Synthese und Kristallstruktur des Nitridokomplexes [Na-15-Krone-5]2[MoNF4]2 · 2 CH3CN

Synthesis and Crystal Structure of the Nitrido Complex [Na-15-crown-5]₂[MoNF₄]₂ · 2 CH₃CN The title compound is synthesized by the reaction of [MoCl₄(NSCl)]₂ with excess NaF in boiling acetonitrile in the presence of the crown ether 15-crown-5. [Na-15-crown-5]₂[MoNF₄]₂ · 2 CH₃CN forms yellow crystals, which were characterized by an X-ray structure determination. Space group P1 , Z = 1. Lattice dimensions at ?90°C: a = 855.5, b = 1 069.9, C = 1 143.5 pm, α = 105.71°, β = 95.29°, γ = 102.25° (4 096 independent observed reflexions, R = 0.039). Short Na…?F contacts of 234 pm with the four axial fluoro ligands of the dimeric anion [MoNF₄]₂^2? allow formulation of a triple ion. The centrosymmetric anion is dimerized by bent fluoro bridges with Mo? F distances of 198 and 245 pm. The long Mo? F distances of the MoF₂Mo ring are in transposition to the nitrido ligands, the bond lengths of which (165 pm) correspond to triple bonds.     

Halogeno-Nitrosylkomplexe von Molybdän und Wolfram. Die Kristallstrukturen von [Na2(15-Krone-5)2(CH3CN)][MoCl4(NO)2] und [Na(15-Krone-5)]2[MoF4Cl(NO)]

Halogeno-Nitrosyl Complexes of Molybdenum and Tungsten. Crystal Structures of [Na₂(15-Crown-5)₂(CH₃CN)][MoCl₄(NO)₂] and [Na(15-Crown-5)]₂[MoF₄Cl(NO)] MoCl₂(NO)₂ and WCl₂(NO)₂, respectively, react with excess sodium fluoride in acetonitrile at room temperature and in the presence of 15-crown-5 to give crystalline mixtures, which consist of the title compounds, respectively of [Na(15-crown-5)]₂[WCl₄(NO)₂] and [Na(15-crown-5)]₂[WF₄Cl(NO)], and which can be separated by selection. The complexes are characterized by their i.r. spectra, the molybdenum compounds additionally by crystal structure determinations. [Na₂(15-crown-5)₂(CH₃CN)][MoCl₄(NO)₂]: Space group P2₁, Z = 2, 5415 independent unique reflexions, R = 0.039. Lattice dimensions at ?10°C: a = 984.3, b = 1231.1, c = 1483.0 pm, β = 105.67°. The compound consists of cations [Ne(l5-crown-5)(CH₃CN)]⁺, in which the sodium ion is surrounded by the five O-atoms of the crown ether and by the N-atom of the acetonitrile molecule, as well as of anions, which form an ion pair {Na(15-crown-5)[MoCl₄(NO)₂]}^?. In the in pairs the sodium ion is coordinated by the five oxygen atoms of the crown ether and by two chlorine atoms of the [MoCI₄(NO)₂]^2? unit. The nitrosyl ligands take the cis-position a t the molybdenum atom which is in a distorted octahedrally fashion. [Na(15-crown-5)]₂[MoF₄Cl(NO)]. Space group C2/c, Z = 4, 1933 independent unique reflexions, R = 0.078. Lattice dimensions at ?7O°C: D : 1.585.8, b = 1171.5, c = 1771.5 pm, β = 114.91°. The compound forms an ion triple, in which the sodium ions are linked to five oxygen atoms each of the crown ether molecules, and to two F-atoms of the [MoF₄Cl(NO)]^2? unit. The F-atom which is arranged in trans-position to the nitrosyl ligand coordinates with both sodium ions; thus an unusual T-shaped arrangement results for this F-atom. The sole terminal F-Atom and the Cl-atom are disordered in two positions.     

Chloroselenate(IV): Darstellung,Struktur und Eigenschaften von [As(C6H5)4]2Se2Cl10 und [As(C6H5)4]Se2Cl9

Chloroselenates(IV): Synthesis, Structure, and Properties of [As(C₆H₅)₄]₂Se₂Cl₁₀ and [As(C₆H₅)₄]Se₂Cl₉ The Se₂Cl₁₀^2? and Se₂Cl₉^? anions were prepared, as the first dinuclear haloselenates(IV), from the reaction of (SeCl₄)₄ with stoichiometric quantities of chloride ions in POCl₃ solutions; they were isolated as yellow crystalline As(C₆H₅)₄⁺ salts. Complete X-ray structural analyses at ?130°C of [As(C₆H₅)₄]₂Se₂Cl₁₀ ( 1 ) (space group P1 , a = 10.296(7), b = 11.271(6), c = 12.375(8) Å, = 74.17(5)°, α = 81.38(5)°, β = 67.69(4)°, V = 1276 ų) and of [As(C₆H₅)₄]Se₂Cl₉ ( 2 ) (space group P2₁/n, a = 12.397(5), b = 17.492(6), c = 14.235(4) Å, α 93.25(3)°, V = 3082 ų) show in both cases two distorted octahedral SeCl₆ groups connected through a common edge in 1 and a common face in 2 . The terminal Se? Cl bonds (average 2.317 Å in 1 , 2.223 Å in 2 ) are much shorter than the Se? Cl bridges (av. 2.661 Å in 1 , 2.652 Å in 2 ). The stereochemical activity of the Se^IV lone electron pair causes severe distortion of the central Se₂Cl₂ ring in the centrosymmetric Se₂Cl₁₀^2? ion. The vibrational spectra of the anions are reported.     

Synthese und Kristallstruktur des μ-Dinitridosulfato(II)-Komplexes [Na-15-Krone-5]2[μ-(NSN)(MoF5)2]

Synthesis and Crystal Structure of the μ-Dinitridosulfate(II) Complex [Na-15-crown-5]₂[μ-(NSN)(MoF₅)₂] The title compound is formed at room temperature by the reaction of [MoCl₄(NSCl)]₂ with the equivalent amount NaF in acetonitrile in presence of the crown ether 15-crown-5. It forms black, moisture-sensitive crystals that were characterized by an X-ray structure determination (1 756 unique observed reflexions, R = 0.073). Crystal data (19°C): a = 965.5, b = 3 219, c = 1 161.1 pm, β = 95.42°; space group P2₁/n, Z = 4. The structure consists of ion triples in which the [Na-15-crown-5]⁺ ions are associated with the [μ-(NSN)(MoF₅)₂]^2? ions via Na…?F contacts of 215 to 265 pm length. Each of the two MoF₅ units of the anion is linked with one of the N atoms of the dinitridosulfate(II) group; bond angle NSN 103°, MoN bond lengths 172 pm.     

THE METASTABLE PARTIALLY POSITIVELY CHARGED Se6 MOLECULE: PREPARATION,CHARACTERISATION AND X-RAY CRYSTAL STRUCTURE OF [Ag2(Se6)(SO2)2][Sb(OTeF5)6]2, [Ag2Se6][AsF6]2 AND [AgSe6][Ag2(SbF6)3]

Reactions designed to give Se₆[Sb(OTeF₅)₆]₂ by the reaction of Se₂Br₂, 4Se, and 2Ag[Sb(OTeF₅)₆] lead to products that include [Ag₂(Se₆)(SO₂)₂][Sb(OTeF₅)₆]₂(1). The distorted cubic (Ag₂Se₆ ²⁺) _n consists of a Se₆ molecule bicapped by two silver cations (local D_3d sym.). Reactions of AgMX₆ (M = As, Sb) with selenium in liquid SO₂ yielded crystals of [Ag₂Se₆][AsF₆]₂ (2) and [AgSe₆][Ag₂(SbF₆)₃] (3). Both salts contain stacked arrays of [AgSe₆]⁺ half-sandwich cationic units. [Ag₂Se₆][AsF₆]₂ in addition contains stronger, linear Se─Ag─Se horizontal linkages between the vertically stacked cationic columns. [AgSe₆][Ag₂(SbF₆)₃] features a remarkable three-dimensional [Ag₂(SbF₆)₃]^? anion held together by strong Sb─F···Ag contacts between component Ag⁺ and SbF₆ ^? ions. Hexagonal channels through this honeycomb-like anion are filled by the stacked [AgSe₆ ⁺]_x.     

Cyclische Polyselenidoarsenate(III) und -antimonate(III): PPh4[Se5AsSe], PPh4[AsSe6–xSx], (PPh4)2[As2Se6] · 2 CH3CN und (PPh4)2[Se6SbSe]2

Cyclic Polyselenidoarsenates(III) and Polyselenidoantimonates(III): PPh₄[Se₅AsSe], PPh₄[AsSe_6–xS _x ], (PPh₄)₂[As₂Se₆] · 2 CH₃CN, and (PPh₄)₂[Se₆SbSe]₂ In acetonitrile, AsCl₃ and sodiumphenolate formed Cl₂AsOPh which then was reacted with PPh₄Se₅ and finally with Na₂Se to yield PPh₄[Se₅AsSe]. With Na₂S instead of Na₂Se, PPh₄[AsSe_6–xS_x] was obtained; the sulfur contents increased with increasing reaction temperature and time (x = 0.21 to 1.09). With PPh₄Se₂ instead of PPh₄Se₅, (PPh₄)₂[1,4-As₂Se₆] · 2 CH₃CN and PPh₄[Se₅AsSe] were the products. With SbCl₃ instead of AsCl₃, (PPh₄)₂[Se₆SbSe]₂ formed. PPh₄[Se₅AsSe] can also be produced from As₂Se₃, PPh₄Br, Na₂Se and selenium in acetonitrile. The crystal structure of PPh₄[SeAsSe₅] is isotypic with PPh₄[S₅AsS] (X-ray structure analysis with 2414 observed reflexions, R = 0.038). The Se₅AsSe^– ion consists of a six-membered AsSe₅ ring in chair conformation, and the As atom has an additional terminal Se atom. The compounds PPh₄[AsSe_6–xS_x] have the same crystal structures, with sulfur atoms taking all selenium positions at random, but with a preference for the terminal position. The anion in (PPh₄)₂[As₂Se₆] · 2 CH₃CN also has a six-membered ring structure in chair conformation, with two arsenic atoms in positions 1 and 4. The centrosymmetric anion in (PPh₄)₂[Se₆SbSe]₂ consists of a central Sb₂Se₂ ring, and a Se₆ ligand is bonded in a chelating manner to each Sb atom (X-ray structure analysis with 2669 observed reflexions, R = 0.099). ⁷⁷Se-NMR spectra are reported.     

Chalkogenohalogenogallate(III) und -indate(III): Eine neue Verbindungsklasse in der dritten Hauptgruppe. Synthese und Struktur von [Ph4P]2[In2SX6], [Et4N]3[In3E3Cl6] · MeCN und [Et4N]3[Ga3S3Cl6] · THF (X = Cl,Br; E = S,Se)

Chalcogenohalogenogallates(III) and -indates(III): A New Class of Compounds for Elements of the Third Main Group. Preparation and Structure of [Ph₄P]₂[In₂SX₆], [Et₄N]₃[In₃E₃Cl₆] · MeCN and [Et₄N]₃[Ga₃S₃Cl₆] · THF (X = Cl, Br; E = S, Se) [In₂SCl₆]^2?, [In₂SBr₆]^2?, [In₃S₃Cl₆]^3?, [In₃Se₃Cl₆]^3?, and [Ga₃S₃Cl₆]^3? were synthesised as the first known chalcogenohalogeno anions of main group 3 elements. [Ph₄P]₂[In₂SCl₆] ( 1 ) (P1 ; a = 10.876(4) Å, b = 12.711(6) Å, c = 19.634(7) Å, α = 107.21(3)°, β = 96.80(3)°, γ = 109.78(3)°; Z = 2) and [Ph₄P]₂[In₂SBr₆] ( 2 ) (C2/c; a = 48.290(9) Å, b = 11.974(4) Å, c = 17.188(5) Å, β = 93.57(3)°, Z = 8) were prepared by reaction of InX₃, (CH₃)₃SiSSi(CH₃)₃ and Ph₄PX (X = Cl, Br) in acetonitrile. The reaction of MCl₃ (M = Ga, In) with Et₄NSH/Et₄NSeH in acetonitrile gave [Et₄N]₃[In₃S₃Cl₆] · MeCN ( 3 ) (P2₁/c; a = 17.328(4) Å, b = 12.694(3) Å, c = 21.409(4) Å, β = 112.18(1)°, Z = 4), [Et₄N]₃[In₃Se₃Cl₆] · MeCN ( 4 ) (P2₁/c; a = 17.460(4) Å, b = 12.816(2) Å, c = 21.513(4) Å, β = 112.16(2)°, Z = 4), and [Et₄N]₃[Ga₃S₃Cl₆] · THF ( 5 ) (P2₁/n; a = 11.967(3) Å, b = 23.404(9) Å, c = 16.260(3) Å, β = 90.75(2)°, Z = 4). The [In₂SX₆]^2? anions (X = Cl, Br) in 1 and 2 consist of two InSX₃ tetrahedra sharing a common sulfur atom. The frameworks of 3, 4 and 5 each contain a six-membered ring of alternating metal and chalcogen atoms. Two terminal chlorine atoms complete a distorted tetrahedral coordination sphere around each metal atom.