Syntheses of [F5TeNH3][AsF6], [F5TeN(H)Xe][AsF6], and F5TeNF2 and characterization by multi-NMR and Raman spectroscopy and by electronic structure calculations: the X-ray crystal structures of alpha- and beta-F5TeNH2, [F5TeNH3][AsF6], and [F5TeN(H)Xe][AsF6

The salt, [F5TeN(H)Xe][AsF6], has been synthesized in the natural abundance and 99.5% 15N-enriched forms. The F5TeN(H)Xe+ cation has been obtained as the product of the reactions of [F5TeNH3][AsF6] with XeF2 (HF and BrF5 solvents) and F5TeNH2 with [XeF][AsF6] (HF solvent) and characterized in solution by 129Xe, 19F, 125Te, 1H, and 15N NMR spectroscopy at -60 to -30 degrees C. The orange [F5TeN(H)Xe][AsF6] and colorless [F5TeNH3][AsF6] salts were crystallized as a mixture from HF solvent at -35 degrees C and were characterized by Raman spectroscopy at -165 degrees C and by X-ray crystallography. The crystal structure of the low-temperature phase, alpha-F5TeNH2, was obtained by crystallization from liquid SO2 between -50 and -70 degrees C and is fully ordered. The high-temperature phase, beta-F5TeNH2, was obtained by sublimation at room temperature and exhibits a 6-fold disorder. Decomposition of [F5TeN(H)Xe][AsF6] in the solid state was rapid above -30 degrees C. The decomposition of F5TeN(H)Xe+ in HF and BrF5 solution at -33 degrees C proceeded by fluorination at nitrogen to give F5TeNF2 and Xe gas. Electronic structure calculations at the Hartree-Fock and local density-functional theory levels were used to calculate the gas-phase geometries, charges, Mayer bond orders, and Mayer valencies of F5TeNH2, F5TeNH3+, F5TeN(H)Xe+, [F5TeN(H)Xe][AsF6], F5TeNF2, and F5TeN2- and to assign their experimental vibrational frequencies. The F5TeN(H)Xe+ and the ion pair, [F5TeN(H)Xe][AsF6], systems were also calculated at the MP2 and gradient-corrected (B3LYP) levels.     

The Simultaneous Oxidation of Tellurium and Transition Metals by AsF5 – Syntheses and Crystal Structures of [M(SO2)6](Te6)[AsF6]6 (M = Ni,Zn) and [Cd(SO2)2][AsF6]2

The reactions of elemental nickel and tellurium and of ZnTe with excess AsF₅ in liquid SO₂ yield [M(SO₂)₆](Te₆)[AsF₆]₆ (M = Ni, Zn) as orange crystals. The crystal structure determinations (triclinic, , M = Ni: a = 1632.59(2), b = 1795.06(1), c = 1822.97(2) pm, α = 119.11(4), β = 90.78(4), γ = 106.28(4)°, V = 4408.24(8)·10⁶pm³, Z = 4) show the two compounds to be isotypic. The structures are made up of discrete [M(SO₂)₆]²⁺ complexes, Te₆⁴⁺ clusters and octahedral [AsF₆]^? ions. In the [M(SO₂)₆]²⁺ complexes the metal ions are surrounded octahedrally by six SO₂ molecules bound via the O atoms. The Te₆⁴⁺ polycations are of trigonal prismatic shape with short Te–Te bonds within the triangular faces (270 pm) and long Te–Te bonds along the edges parallel to the pseudo C₃ axes of the prisms (312 pm). The arrangement of the ions is related to the Li₃Bi structure type. [M(SO₂)₆]²⁺ complexes and Te₆⁴⁺ polycations together form a distorted cubic closest packing with all tetrahedral and octahedral interstices filled by [AsF₆]^? ions. The analogous reaction starting from CdTe did not yield a compound containing simultaneously [Cd(SO₂)_n]²⁺ complexes and tellurium polycations but instead Te₆[AsF₆]₄ · 2 SO₂ besides [Cd(SO₂)₂][AsF₆]₂ were obtained. It crystallizes isotypically to [Mn(SO₂)₂][AsF₆]₂ (Mews, Zemva, 2001) (orthorhombic, Fdd2, a = 1534.96(3), b = 1812.89(3), c = 892.28(3) pm, V = 2483·10⁶ pm³, Z = 4).     

Bi6F11]7+--an unusual, highly charged bismuth fluoro complex in (Se4)[Bi6F11][AsF6]9.10 SO2

A unique, highly charged cationic bismuth fluoro cluster [Bi6F11]7+, embedded in the complex crystal structure of (Se4)2+[Bi6F11]7+[AsF6-]9.10 SO2, was synthesized from Bi2Se3 and AsF5 in liquid SO2.     

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.     

Synthese,Struktur und Phasenumwandlung von Te4[AsF6]2·SO2

Synthesis, Crystal Structure, and Solid State Phase Transition of Te₄[AsF₆]₂·SO₂ The oxidation of tellurium with AsF₅ in liquid SO₂ yields Te₄²⁺[AsF₆^—]₂ which can be crystallized from the solution in form of dark red crystals as the SO₂ solvate. The crystals are very sensitive against air and easily lose SO₂, so handling under SO₂ atmosphere or cooling is required. The crystal structure was determined at ambient temperature, at 153 K, and at 98 K. Above 127 K Te₄[AsF₆]₂·SO₂ crystallizes orthorhombic (Pnma, a = 899.2(1), b = 978.79(6), c = 1871.61(1) pm, V = 1647.13(2)·10⁶pm³ at 297 K, Z = 4). The structure consists of square‐planar Te₄²⁺ ions (Te‐Te 266 pm), octahedral [AsF₆]^— ions and of SO₂ molecules which coordinate the Te₄ rings with their O atoms in bridging positions over the edges of the square. At room temperature one of the two crystallographically independent [AsF₆]^— ions shows rotational disorder which on cooling to 153 K is not completely resolved. At 127 K Te₄[AsF₆]₂·SO₂ undergoes a solid state phase transition into a monoclinic structure (P112₁/a, a = 866.17(8), b = 983.93(5), c = 1869.10(6) pm, γ = 96.36(2)°, V = 1554, 2(2)·10⁶ pm³ at 98 K, Z = 4). All [AsF₆]^— ions are ordered in the low temperature form. Despite a direct supergroup‐subgroup relationship exists between the space groups, the phase transition is of first order with discontinuous changes in the lattice parameters. The phase transition is accompanied by crystal twinning. The main difference between the two structures lies in the different coordination of the Te₄²⁺ ion by O and F atoms of neighbored SO₂ and [AsF₆]^— molecules.     

Syntheses and X-ray crystal structures of alpha- and beta-[XeO2F][SbF6], [XeO2F][AsF6], [FO2XeFXeO2F][AsF6], and [XeF5][SbF6)].XeOF4 and computational studies of the XeO2F+ and FO2XeFXeO2F+ cations and related species

Reactions of XeO2F2 with the strong fluoride ion acceptors, AsF5 and SbF5, in anhydrous HF solvent give rise to alpha- and beta-[XeO2F][SbF6], [XeO2F][AsF6], and [FO2XeFXeO2F][AsF6]. The crystal structures of alpha-[XeO2F][SbF6] and [XeO2F][AsF6] consist of trigonal-pyramidal XeO2F+ cations, which are consistent with an AXY2E VSEPR arrangement, and distorted octahedral MF6- (M = As, Sb) anions. The beta-phase of [XeO2F][SbF6] is a tetramer in which the xenon atoms of four XeO2F+ cations and the antimony atoms of four SbF6- anions are positioned at alternate corners of a cube. The FO2XeFXeO2F+ cations of [FO(2)XeFXeO2F][AsF6] are comprised of two XeO2F units that are bridged by a fluorine atom, providing a bent Xe- - -F- - -Xe arrangement. The angle subtended by the bridging fluorine atom, a xenon atom, and the terminal fluorine atom of the XeO2F group is bent toward the valence electron lone-pair domain on xenon, so that each F- - -XeO2F moiety resembles the AX(2)Y(2)E arrangement and geometry of the parent XeO2F2 molecule. Reaction of XeF6 with [H3O][SbF6] in a 1:2 molar ratio in anhydrous HF predominantly yielded [XeF5][SbF6].XeOF4 as well as [XeO2F][Sb2F11]. The crystal structure of the former salt was also determined. The energy-minimized, gas-phase MP2 geometries for the XeO2F+ and FO2XeFXeO2F+ cations are compared with the experimental and calculated geometries of the related species IO2F, TeO2F-, XeO2(OTeF5)+, XeO2F2, and XeO2(OTeF5)2. The bonding in these species has been described by natural bond orbital and electron localization function analyses. The standard enthalpies and Gibbs free energies for reactions leading to XeO2F+ and FO2XeFXeO2F+ salts from MF5 (M = As, Sb) and XeO2F2 were obtained from Born-Haber cycles and are mildly exothermic and positive, respectively. When the reactions are carried out in anhydrous HF at low temperatures, the salts are readily formed and crystallized from the reaction medium. With the exception of [XeO2F][AsF6], the XeO2F+ and FO2XeFXeO2F+ salts are kinetically stable toward dissociation to XeO2F2 and MF5 at room temperature. The salt, [XeO2F][AsF6], readily dissociates to [FO2XeFXeO2F][AsF6] and AsF5 under dynamic vacuum at 0 degree C. The decompositions of XeO2F+ salts to the corresponding XeF+ salts and O2 are exothermic and spontaneous but slow at room temperature.     

Tetrachloro- and tetrabromoarsonium(V) cations: raman and 75As, 19F NMR spectroscopic characterization and X-ray crystal structures of [AsCl4][As(OTeF5)6] and [AsBr4][AsF(OTeF5)5]

The salts [AsX4][As(OTeF5)6] and [AsBr4][AsF(OTeF5)5] (X = Cl, Br) have been prepared by oxidation of AsX3 with XOTeF5 in the presence of the OTeF5 acceptors As(OTeF5)5 and AsF(OTeF5)4. The mixed salts [AsCl4][Sb(OTeF5)6-nCl(n-2)] and [AsCl4][Sb(OTeF5)6-nCl(n)] (n > or = 2) have also been prepared. The AsBr4+ cation has been fully structurally characterized for the first time in SO2ClF solution by 75As NMR spectroscopy and in the solid state by a single-crystal X-ray diffraction study of [AsBr4][AsF(OTeFs)5]: P1, a = 9.778(4) A, b = 17.731(7) A, c = 18.870(8) A, alpha = 103.53(4)degrees, beta = 103.53(4) degrees, gamma = 105.10(4) degrees, V = 2915(2) A3, Z = 4, and R1 = 0.0368 at -183 degrees C. The crystal structure determination and solution 75As NMR study of the related [AsCl4][As(OTeF5)6] salt have also been carried out: [AsCl4][As(OTeF5)6], R3, a = 9.8741(14) A, c = 55.301(11) A, V= 4669(1) A3, Z = 6, and R1 = 0.0438 at -123 degrees C; and R3, a = 19.688(3) A, c = 55.264(11) A, V= 18552(5) A3, Z = 24, and R1 = 0.1341 at -183 degrees C. The crystal structure of the As(OTeF5)6- salt reveals weaker interactions between the anion and cation than in the previously known AsF6- salt. The AsF(OTeF5)5- anion is reported for the first time and is also weakly coordinating with respect to the AsBr4+ cation. Both cations are undistorted tetrahedra with bond lengths of 2.041(5)-2.056(3) A for AsCl4+ and 2.225(2)-2.236(2) A for AsBr4+. The Raman spectra are consistent with undistorted AsX4+ tetrahedra and have been assigned under Td point symmetry. The 35Cl/37Cl isotope shifts have been observed and assigned for AsCl4+, and the geometrical parameters and vibrational frequencies of all known and presently unknown PnX4+ (Pn = P, As, Sb, Bi; X = F, Cl, Br, I) cations have been calculated using density functional theory methods.     

Coordination compounds with the general formula trans-[M(18-crown-6)(C5HO2F6)2] as structural-thermochemical analogs. The complexes trans-[Pb(18-crown-6)(C5HO2F6)2] and trans-[Ba(18-crown-6)(C5HO2F6)2]

The molecular geometries of the complexes trans-[M(18-crown-6)(C₅HO₂F₆)₂] (where M = Ca, Sr, Ba (I), Zn, Cd, Sn, Pb (II), Fe, Co, Eu, and Yb) were modeled by the molecular mechanics method with fixed R(M-O) distances. The shielding degrees of the central metal atom in these complexes were calculated and the number and types of possible intermolecular contacts between their molecules in the structure were determined. The intermolecular interactions involve identical fragments (atoms) of the ligands: the CF₃ groups of the hexafluoroacetylacetonate ligands and the methylene fragments of the crown ether. Previously unknown complex II and complex I were synthesized according to an original procedure. The structure and thermochemical properties (including sublimation by the Knudsen method) of complex II were studied. As in complex I, the metal cation in complex II is in the cavity of the macrocycle of the crown ether; the hexafluoroacetylacetonate ligands are trans relative to that cation. The presumed similarity of complexes I and II in thermochemical characteristics was confirmed experimentally. Both the complexes melt in close temperature intervals and sublime at the same temperature (～10^?2 mm Hg) without decomposition. The enthalpies of sublimation of complexes I and II, as well as the entropy contributions to their volatilities, are equal to within the experimental error.     

C6F5XeCl and [(C6F5Xe)2Cl][AsF6]: The First Isolated and Unambiguously Characterized Xenon(II) Chlorine Compounds

Xenon(II ) chlorine compounds can be obtained as the isolable organo derivatives C₆F₅XeCl and [(C₆F₅Xe)₂Cl][AsF₆] (whose cation is depicted) in 85 and 91 % yield, respectively. These compounds decompose vigorously at 36°C and 100°C, respectively, leading to the formation of C₆F₅Cl and Xe gas and of C₆F₅Cl, C₆F₆, and [C₆F₅Xe][AsF₆], respectively.     

Anionische Antimon(III)-Fluorokomplexe mit protonierten Azakronenethern als Gegenionen. Strukturen und Mößbauerspektren von [H2cyclam]2[Sb4F16] · 2 H2O, [H4cyclam][Sb2F10] · 2 HF und [H4(tetramethyl)cyclam]2[Sb4F15][HF2][F]4 (cyclam = 1,4,7,11-Tetraazacyclotetradecan)

Anionic Antimony(III) Fluoro Complexes with protonated Azacrownethers as Counterions. Crystal Structures and Mößbauer Spectra of [H₂cyclam]₂[Sb₄F₁₆] · 2H₂O, [H₄cyclam][Sb₂F₁₀] · 2 HF, and [H₄(tetramethyl)cyclam]₂[Sb₄F₁₅][HF₂][F]₄ (cyclam = 1,4,7,11-Tetraazacyclotetradecane) The title compounds are formed by reaction of SbF₃ with the respective azacrownether. [H₂cyclam]₂[Sb₄F₁₆] · 2 H₂O contains tetrameric anions which weakly associate to chains. The [H₂cyclam]²⁺ ions possess an unusual conformation due to intramolecular hydrogen bonds. [H₄cyclam][Sb₂F₁₀] · 2HF contains the dimeric hitherto unknown [Sb₂F₁₀]^4? ion; two HF molecules are attached to it by hydrogen bonds. The structure of [H₄(tetramethyl)cyclam]₂[Sb₄F₁₅][HF₂][F]₄ is made up of the two dimensional polymeric [HSb₄F₁₇]^4? anion. The tetra-protonated tetramethylcyclam ions form host-guest complexes with fluoride ions.     

Crystal structure and single crystal EPR of (NH4)2(15-crown-5)3[Cu(mnt)2] and (NH4)2(benzo-15-crown-5)4[Cu(mnt)2]·0.5H2O

The X-ray crystal structures of (NH4)2(15-crown-5)3[Cu(mnt)2] (1) and (NH4)2(benzo-15-crown-5)4- [Cu(mnt)2]·0.5H2O (2) were determined. Two single crystals are composed of distinct structures of ammonium-crown ether supramolecular cation and [Cu(mnt)2]2- anion. The triple-decker dication in complex 1 and a sandwich dimmer in complex 2 were observed. X-Band EPR studies on the single crystals of both complex 1 and complex 2 have been carried out at room temperature, which revealed that complex 2 showed a perfect hyperfine structure of Cu whereas that of complex 1 could not be observed. The principal values and direction cosines of the principal axes of the g and A tensors were computed by a least-squares fitting procedure. The spin density of Cu(Ⅱ) was estimated according to the principal values of the A tensors and compared well with the results calculated based on DFT method.     

Stabilization of the P(CF3)(2)(-) and P(C6F5)(2)(-) ions by coordination to pentacarbonyl tungsten: structures of [18-crown-6-K]P(CF3)2, [18-crown-6-K][W[P(CF3)2](CO)5], and [18-crown-6-K][[W(CO)5]2[mu-P(C6F5)2]].THF

The stabilization of the P(CF(3))(2)(-) ion by intermediary coordination to the very weak Lewis acid acetone gives access to single crystals of [18-crown-6-K]P(CF(3))(2). The X-ray single crystal analysis exhibits nearly isolated P(CF(3))(2)(-) ions with an unusually short P-C distance of 184(1) pm, which can be explained by negative hyperconjugation and is also found by quantum chemical hybrid DFT calculation. Coordination of the P(CF(3))(2)(-) ion to pentacarbonyl tungsten has only a minor effect on electronic and geometric properties of the P(CF(3))(2) moiety, while a strong increase in thermal stability of the dissolved species is achieved. The hitherto unknown P(C(6)F(5))(2)(-) ion is stabilized by coordination to pentacarbonyl tungsten and isolated as a stable 18-crown-6 potassium salt, [18-crown-6-K][W[P(C(6)F(5))(2)](CO)(5)], which is fully characterized. The tungstate, [W[P(C(6)F(5))(2)](CO)(5)](-), decomposes slowly in solution, while coordination of the phosphorus atom to a second pentacarbonyl tungsten moiety results in an enhanced thermal stability in solution. The single-crystal X-ray analysis of [18-crown-6-K][[W(CO)(5)](2)[mu-P(C(6)F(5))(2)]].THF exhibits a very tight arrangement of the two C(6)F(5) and two W(CO)(5) groups around the central phosphorus atom. NMR spectroscopic investigations of the [[W(CO)(5)](2)[mu-P(C(6)F(5))(2)]](-) ion exhibit a hindered rotation of both the C(6)F(5) and W(CO)(5) groups in solution.     

Syntheses and solid-state and solution structures of [Ba[(C5Me5)2Ti2F7]2(hmpa)] and [Ba8Ti6F30I2(C5Me5)6(hmpa)6][I3]2

The complexes [Ba[(C5Me5)2Ti2F7]2(hmpa)].(THF), 1.hmpa.(THF), and [Ba8Ti6F30I2(C5Me5)6(hmpa)6][I3]2.10(THF), 2[I3]2.10(THF), were prepared from [Hdmpy](+)[(C5Me5)2Ti2F7]- (dmpy = 2,6-dimethylpyridine), BaI2, and hmpa (hmpa = hexamethylphosphoramide). They were characterized by 1H and 19F NMR and IR spectroscopy and examined by single-crystal X-ray crystallography. The complexation equilibrium of the barium ion in 1 with hmpa and the dynamics of the barium ion moving on the fluorine surfaces of [(C5Me5)2Ti2F7]- in 1.hmpa have been studied by variable-temperature 19F NMR spectroscopy. The core of the complex 2[I3]2.10(THF) resembles the basic structural unit of the cubic perovskite.     

Synthese und Kristallstruktur von [Cr(NH3)6][Cr(NH3)2F4][BF4]2

Synthesis and Crystal Structure of [Cr(NH₃)₆][Cr(NH₃)₂F₄][BF₄]₂ The action of ammonium fluoride on a mixture of boron and chromium in a sealed Monel ampoule at 300 °C yields single crystals of [Cr(NH₃)₆][Cr(NH₃)₂F₄][BF₄]₂. The crystal structure (tetragonal, P4/mbm, Z = 2, a = 1056.0(1), c = 781.7(1) pm; R₁ = 0.0414; wR₂ = 0.1087 for 411 reflections with I₀ > 2σ(I)) contains [Cr(NH₃)₆]³⁺ and [Cr(NH₃)₂F₄]^– octahedra and twice as many [BF₄]^– tetrahedra that are arranged in a quadrupled super‐structure of the CsCl‐type of structure.     

Polycations Stabilised by Borosulfates: [Au3Cl4][B(S2O7)2] and the One-Dimensional Metal [Au2Cl4][B(S2O7)2](SO3)

(SO₄)-rich silicate analogue borosulfates are able to stabilise cationic cluster-like and chain-like aggregates. Single crystals of [Au₃Cl₄][B(S₂O₇)₂] and [Au₂Cl₄][B(S₂O₇)₂](SO₃) were obtained by solvothermal reaction with SO₃, and the electronic properties were investigated by means of density functional theory–based calculations. [Au₃Cl₄][B(S₂O₇)₂] exhibits a cluster-like cation, and the cationic gold-chloride strands in [Au₂Cl₄][B(S₂O₇)₂](SO₃) are found to resemble one-dimensional metallic wires. This is confirmed by polarisation microscopy.     

Halogenomercurate: Darstellung und Strukturen von [Cu(en)2][Hg2Cl6], [Cu(en)2][Hg2Br6] und [Cu(en)2][HgBr4]

Halomercurates: Syntheses and Crystal Structures of [Cu(en)₂][Hg₂Cl₆], [Cu(en)₂][Hg₂Br₆], and [Cu(en)₂][HgBr₄] Crystals of [Cu(en)₂][Hg₂Cl₆] ( 1 ) have been obtained by layering a solution of Hg(NO₃)₂ and NaCl with a solution of [Cu(en)₂]SO₄. An analogous procedure, using NaBr instead of NaCl, gave crystals of [Cu(en)₂][HgBr₄] ( 3 ). Crystals of [Cu(en)₂][Hg₂Br₆] ( 2 ) were obtained by gel crystallization using the same starting materials as for 3 . The complexes show very low solubility. The dinuclear anions of 1 consist of two nearly planar HgCl₃ units related by a center of symmetry. In 2 infinite anionic chains are present, made up of parallel HgBr₃ units. These units are packed in such a way as to produce a trigonal bipyramidal configuration around the Hg atoms. 3 contains mononuclear deformed tetrahedral [HgBr₄]^2– anions. In all three complexes the packing of the ions is such that halogen atoms of halomercurate anions complete a tetragonal bipyramidal coordination at Cu. The resulting Cu–Halogen distances are 2.924 Å for 1 , 3.036 Å for 2 and 3.085 and 3.119 Å for 3 . 1 : Space group P 1, Z = 1, lattice constants at 20 °C: a = 7.000(2), b = 7.526(2), c = 8.239(2) Å; α = 88.39(2), β = 86.06(2), γ = 86.10(3)°; R₁ = 0.040. 2 : Space group P2₁/c, Z = 2, lattice constants at –50 °C: a = 7.185(1), b = 16.338(2), c = 7.814(1) Å; β = 94.88(2)°; R₁ = 0.033. 3 : Space group P2₁/n, Z = 4, lattice constants at 20 °C: a = 8.055(3), b = 13.101(3), c = 13.814(3) Å; β = 91.24(3)°; R₁ = 0.092.