Synthese,Kristallstruktur und Eigenschaften von Na2RbAuO2

Synthesis, Crystal Structure, and Properties of Na₂RbAuO₂ Single phase samples of Na₂RbAuO₂ were prepared by reacting RbAu with Na₂O₂ in an equimolar ratio in sealed silver cylinders (placed under argon in glas tubes) at 400 °C for two weeks. The colourless single crystals of needle shaped habitus decompose immediately when exposed to air. Na₂RbAuO₂ (Pearsoncode oP12, Pnnm, a = 992.76(6), b = 559.03(3), c = 408.64(3) pm, Z = 2, 414 reflections with I_o > 2σ(I), R₁ = 0.0363, wR₂ = 0.1057) crystallizes isotypic with Na₂KAuO₂. Besides linear [O–Au–O] units, which are characteristic for oxoaurates(I), the structure reveals uncommon low coordination numbers for the alkali metal cations.     

Synthese und Kristallstruktur von KTeOF3

Synthesis and Crystal Structure of KTeOF₃ KTeOF₃ has been synthesized by solid state reaction of KF, TeO₂ and KTeF₅ in equimolar amounts. Its crystal structure has been solved by single crystal structure analysis (P4₂/n, a = 1007.96(3), c = 789.58(3) pm, Z = 8, R₁ = 0.0311). As a characteristic feature, the compound contains unprecedented dimeric anions Te₂O₂F₆^2– formed by two edge‐sharing pseudo‐octahedral units. IR and Raman data are given.     

Synthese und Kristallstruktur von K2Mn3S4

Synthesis and Crystal Structure of K₂Mn₃S₄ Single crystals of K₂Mn₃S₄ have been prepared by a fusion reaction of potassium carbonate with manganese in a stream of hydrogen sulfide at 900 °C. K₂Mn₃S₄ crystallizes in a new monoclinic layered structure type (P2/c, a = 7.244(2) Å, b = 5.822(1) Å, c = 11.018(5) Å, β = 112.33(3)°, Z = 2) which can be described as a stacking variant of the orthorhombic Cs₂Mn₃S₄ structure type. Measurements of the magnetic susceptibilities show antiferro‐magnetic interactions.     

Na2C2 und K2C2: Synthese,Kristallstruktur und spektroskopische Eigenschaften

Na₂C₂ and K₂C₂: Synthesis, Crystal Structure, and Spectroscopic Properties By the reaction of sodium or potassium solved in liquid ammonia with acetylene and subsequent heating in high vacuum Na₂C₂ and K₂C₂ could be synthesised as single phase products. The crystal structures described by Föppl could be confirmed by X-ray and neutron diffraction experiments (K₂C₂) on powdered samples. Both compounds crystallise in a tetragonal structure (I4₁/acd, no. 142, Z = 8) which can be described as a distorted variant of the antifluorite-structure type. At temperatures above room temperature (Na₂C₂: 580 K, K₂C₂: 420 K) a reversible phase transition (1^st order transition) to a cubic modification (Fm 3 m, no. 225, Z = 4) has been observed, analogous to the alkaline earth metal acetylides. This high temperature modification represents an undistorted antifluorite structure with disordered C₂^2– dumbbells. The results of raman- and ¹³C-MAS-NMR-spectroscopic investigations are in agreement with acetylide dumbbells in the title compounds and allow a comparison to the respective monoalkalimetal and alkaline earth metal acetylides.     

Hochdruck‐Synthese,Kristallstruktur und Eigenschaften von NaPN2

High‐Pressure Synthesis, Crystal Structure, and Properties of NaPN₂ Single phase NaPN₂ was synthesized by the reaction of NaN₃ and P₃N₅ in a multianvil assembly at 3 GPa and 1000 °C. The title compound crystallizes in a variant of the chalcopyrite structure type and is isotypic to LiPN₂. The crystal structure was refined by the Rietveld method (I 4 2d, a = 497.21(2), c = 697.60(3) pm, Z = 4, 36 observed reflections, R_p = 0.0502, wR_p = 0.0649, R_F = 0.0788).     

Darstellung und Kristallstruktur von NaBi2AuO5

Synthesis and Crystal Structure of NaBi₂AuO₅ NaBi₂AuO₅ was obtained by hydrothermal reaction of ‘Bi₂O₅’, Au₂O₃ · 2H₂O and saturated aqueous NaOH solution at temperatures from 300 to 600°C and oxygen pressure from 3 × 10⁸ to 6 × 10⁸ Pa for the first time. The crystal structure (P4 b2; a = 1 220.02(6) pm; b = 386.68(3) pm; Z = 4; R_w = 0.022) consists of bisphenoidic distorted AuO₄ groups, which are stacked in c-direction. They are connected by square pyramidal BiO₅ units. Sodium is occupying holes within the Au/Bi/O framework thus formed.     

Synthese und Kristallstruktur des Goldclusters [Au16(AsPh3)8Cl6]

Synthesis and Structures of the Gold Cluster [Au₁₆(AsPh₃)₈Cl₆] Reduction of Ph₃AsAuCl with NaBH₄ in ethanol yields the gold cluster [Au₁₆(AsPh₃)₈Cl₆]. It can be crystallized from dichloromethane/diisopropyl ether in form of dark red, light sensitive crystals with the space group P2₁/n and a = 1777.68(8), b = 3372.7(1), c = 2696.2(1)pm, β = 94.166(6)°, Z = 4). The inner skeleton of the 16 Au atoms consists of a centered icosahedron of which one of the corners binds to three additional Au atoms forming a tetrahedron pendent. The shortest Au–Au distances of 264.3 to 266.6 pm correspond to the bonds to the three external Au atoms. Within the icosahedron the distances between the central atom and the peripheral atoms (273.0–279.1 pm) are distinctly shorter than the distances between the peripheral atoms (283.6–299.0 pm).     

Synthese und Kristallstruktur von Cs3Y7Se12

Synthesis and Crystal Structure of Cs₃Y₇Se₁₂ The oxidation of yttrium metal with selenium in the presence of CsCl (7 d, 700°C, evacuated silicia tubes) results in the formation of pale yellow, lath-shaped single crystals of Cs₃Y₇Se₁₂. The crystal structure (orthorhombic, Pnnm, Z = 2, a = 1272.8(3), b = 2627.7(5), c = 413.32(8) pm) consists of edge- and vertex-connected [YSe₆] octahedra forming a rocksalt-related network [Y₇Se₁₂]^3?. One-dimensional infinite channels along [001], apt to take up extra cations, provide coordination numbers of 6 and 7 + 1, respectively, for two crystallographically different Cs⁺.     

Synthese und Kristallstruktur von LiHSO4

Synthesis and Crystal Structure of LiHSO₄ Single crystals of the new compound LiHSO₄ are synthezised from the system Lithiumsulfate/Sulfuric acid. The up to day not determined structure of the title compound is monoclinic, space group P2₁/c with the lattice constants a = 5.234(2), b = 7.322(1) and c = 8.363(1) Å, b? = 90.02(2)°. The volume of the unit cell has been determined to V = 320.5 ų, the number of formula units to Z = 4 and the density to D_x = 2.156 g cm^?3. There are crystallographically identical SO₃(OH)- and LiO₄-tetrahedra in the structure. Every tetraheda is linked to four different tetrahedra of the other sort. Two neighboured LiO4 terahedra form a common edge. In that way layers are formed running parallel the yz-plane. These layers are connected over hydrogen bonds.     

Synthese und Kristallstruktur von Sr2Rh7P6

Synthesis and Crystal Structure of Sr₂Rh₇P₆ Single crystals of Sr₂Rh₇P₆ were obtained by reaction of the elements in molten lead at 1100 °C and investigated by X-ray methods. The compound crystallizes tetragonally (a = 11.080(2), c = 4.098(1) Å) and forms a crystal structure (P 4 2₁m; Z = 2) with ThCr₂Si₂ analogous units, which are linked with each other in a new way. Therefore the RhP₄ tetrahedra form bands of edge sharing chains parallel to [001] anstead of layers as in the ThCr₂Si₂ type structure. The arrangement enables a part of the P atoms to form short P–P distances of 2,26 Å and space for additional Rh atoms with a likewise distorted tetrahedral coordination of P atoms is obtained.     

Darstellung und Kristallstruktur von Cs4SnO3

Preparation and Crystal Structure of Cs₄SnO₃ Crystals of Cs₄SnO₃ were synthesized by reaction of SnO with elemental Cs. The compound crystallizes with the triclinic spacegroup P1 with lattice constants a = 737.61(9) pm, b = 1171.3(1) pm, c = 1199.2(1) pm, α = 66.08(3)°, β = 80.88(2)°, γ = 82.28(3)° and Z = 4. The crystal structure exhibits isolated stannate(II) ions [Sn^IIO₃]^4– of ψ-tetrahedral form. Whereas a new structure type is present, there is a close relationship with the structures of the Cs stanntates and plumbates(IV).     

Darstellung und Kristallstruktur von Rb4Br2O und Rb6Br4O

Syntheses and Crystal Structures of Rb₄Br₂O and Rb₆Br₄O In the quasi‐binary system RbBr/Rb₂O, the addition compounds Rb₄Br₂O and Rb₆Br₄O are obtained by solid state reaction of the boundary components RbBr and Rb₂O. Crystals of red‐orange Rb₄Br₂O as well as of orange Rb₆Br₄O decompose immediately when exposed to air. Rb₄Br₂O (Pearson code tI14, I4/mmm, a = 544.4(6) pm, c = 1725(2) pm, Z = 2, 175 symmetry independent reflections with I_o > 2σ(I), R₁= 0.0618) crystallizes in the anti K₂NiF₄ structure type; Rb₆Br₄O (Pearson code hR22, R3c, a = 1307.8(3) pm, c = 1646.6(5) pm, Z = 6, 630 symmetry independent reflections with I_o > 2σ(I), R₁ = 0.0759) in the anti K₄CdCl₆ structure type. Both structures contain characteristic ORb₆‐octahedra and can be understood as expanded perovskites, following the general systematics of alkaline metal oxide halides.     

Zur Kristallstruktur von Rb2C2 und Cs2C2

On the Crystal Structure of Rb₂C₂ and Cs₂C₂ By reaction of rubidium or caesium solved in liquid ammonia with acetylene AC₂H with A = Rb, Cs was obtained, which was subsequently converted into the binary acetylide A₂C₂ in vacuum at temperatures of 520 K (Rb₂C₂) and 470 K (Cs₂C₂) using a surplus of the respective alkali metal. The crystal structures of the very air sensitive compounds were solved and refined by a combination of both neutron and X‐ray powder diffraction data. Rb₂C₂ as well as Cs₂C₂ coexist in two modifications. The hexagonal modification (P 6 2m, Z = 3) crystallises in the known Na₂O₂ structure type with two crystallographic independent sites for the C₂^2– dumbbells. For the orthorhombic modification (Pnma, Z = 4) a new structure type was found, which is related to the PbCl₂ structure type with ordered C₂^2– dumbbells occupying the Pb sites. Temperature dependent investigations between 4 K and the decomposition temperature by the means of neutron and X‐ray powder diffraction resulted in a very complex dynamic disorder of the C₂ dumbbells, which is still not completely understood. The frequencies of the C–C stretching vibration determined by the help of Raman spectroscopy fit nicely to the results obtained for other alkali metal acetylides and alkali metal hydrogen acetylides. These results seem to indicate that the electronegativity of the alkali metal has a strong influence on the frequency of the C–C stretching vibration.     

Synthese und Kristallstruktur von Bi2ErO4I

Synthesis and Crystal Structure of Bi₂ErO₄I Bi₂ErO₄I was prepared by solid‐state reaction of stoichiometric mixture of BiOI, Bi₂O₃ and Er₂O₃. Bi₂ErO₄I is a new compound and the first bismuth rare earth oxide iodide. The crystal structure was determined by the Rietveldmethod (P4/mmm, a = 3,8896(6) Å, c = 9,554(2) Å, Z = 1). In this structure [M₃O₄]⁺‐layers are interleaved by single I^–‐layers. Er and Bi atoms of Bi₂ErO₄I are 8‐coordinated. The structure can be derived from the LiBi₃O₄Cl₂‐structure type.     

Zur Kenntnis von LiSi2N3: Synthese und Verfeinerung der Kristallstruktur

On LiSi₂N₃ – Synthesis and Crystal Structure Refinement Single-crystalline LiSi₂N₃ was obtained by the reaction of lithium and silicon diimide under N₂ atmosphere in a radio-frequency furnace at 1300 °C. LiSi₂N₃ is isotypic with Li₂SiO₃ and it crystallizes as an ordered variant of wurtzite. A single-crystal X-ray diffraction analysis (Cmc2₁, a = 922.15(9), b = 529.64(8), c = 477.98(5) pm, Z = 4, R1 = 0.0173, wR2 = 0.0382) confirms and improves the structural data which previously had been obtained from powder diffraction data.     

Wasserfreie Selenite des Lanthans: Synthese und Kristallstruktur von La2(SeO3)3 und LaFSeO3

Anhydrous Selenites of Lanthanum: Syntheses and Crystal Structures of La₂(SeO₃)₃ and LaFSeO₃ Colorless single crystals of La₂(SeO₃)₃ were obtained via the decomposition of La₂(SeO₄)₃ in the presence of NaCl in sealed gold ampoules. The compound crystallizes in the orthorhombic system (Pnma, Z = 4, a = 846.7(1), b = 1428.6(1), c = 710.3(2) pm, R_all = 0.0223) and contains La³⁺ in tenfold coordination of oxygen atoms which belong to seven SeO₃^2– groups. Hence, three of the latter act as bidentate ligands. The reaction of LiF with La₂(SeO₄)₃ in sealed gold ampoules yielded colorless single crystals of LaFSeO₃ (monoclinic, P2₁/c, Z = 12, a = 1819.8(3), b = 715.75(8), c = 846.4(1) pm, β = 96.89(2)°, R_all = 0.0352). The crystal structure contains three crystallographically different La³⁺ ions. La1 is surrounded by six oxygen atoms from five SeO₃^2– groups and four fluoride ions, La2 is coordinated by two bidentate SeO₃^2– ions and seven fluoride ligands. La3 is surrounded by oxygen atoms only with the coordination number and polyhedron being almost the same as found for La³⁺ in La₂(SeO₃)₃. Furthermore, the crystal structures of both compounds are strongly influenced by the lone pairs of the SeO₃^2– groups.     

Synthese und Kristallstruktur von CsAu(SO4)2

Synthesis and Crystal Structure of CsAu(SO₄)₂ Light yellow single crystals of CsAu(SO₄)₂ were obtained upon evaporation of a solution of Au(OH)₃ and Cs₂SO₄ in sulfuric acid (96 % H₂SO₄). In the crystal structure (monoclinic, P2₁/c, Z = 4, a = 1029.7(2), b = 893.4(2), c = 901.0(1) pm, β = 111.08(1)°) Au³⁺ is in square planar coordination of oxygen atoms which belong to four SO₄^— ions. According to [Au(SO₄)_4/2]^— puckered layers are formed which are connected by the Cs⁺ ions. The latter are surrounded by five chelating and three monodentate sulfate groups leading to a CN of 13.     

Synthese und Kristallstruktur von (PPh4)2Se6

Synthesis and Crystal Structure of (PPh₄)₂Se₆ (PPh₄)₂Se₆ has been prepared by the reaction of selenium with K₂Se₂ in dimethylformamide solution in the presence of K₃[Mn(CN)₆] and PPh₄Br, forming black crystal needles. According to the crystal structure determination the compound consists of PPh⁺₄ ions and chainlike hexaselenide ions. Space group P6 , Z = 2,4683 Observed unique reflections, R = 0.066. Lattice dimensions at ?90°C: a = 951.0, b = 1094.8, c = 2137.4 pm, α = 82.66°, β = 83.36°, γ = 89.96°.     

Synthese und Kristallstruktur von Calcium-Kupfer-Diarsenat CaCuAs2O7

Synthesis and Crystal Structure of the Calcium Copper Diarsenate CaCuAs₂O₇ Solid state reactions led to single crystals of CaCuAs₂O₇. X-ray investigations revealed monoclinic symmetry, space group C⁵_2h-P2₁/c, lattice constants a = 7.272(1); b = 8.946(2); c = 9.307(2) Å; β = 109.48(2)°; Z = 4. CaCuAs₂O₇ is characterized by ¹_∞[CaO₆] chains, connected by As₂O₇ double tetrahedra and elongated square CuO₅ pyramids. The hitherto unknown crystal structure shows relationships to CaCuP₂O₇ but not to CaCuV₂O₇.     

Synthese,Kristallstruktur und Festkörper-NMR-spektroskopische Untersuchungen von K5H(CN2)3

Synthesis, Crystal Structure, and Solid State MAS-NMR Spectroscopic Investigation of K₅H(CN₂)₃ Single phase K₅H(CN₂)₃ was synthesized by reaction of KHCN₂ with metallic potassium in liquid ammonia or by reaction of KNH₂ with melamine C₃N₃(NH₂)₃ at 320 °C, respectively. The crystal structure was determined from X-ray powder and single crystal data: K₅H(CN)₃, space group Im3m, a = 795.68(7) pm, Z = 2, R1 = 0.025, wR2 = 0.0438. In the solid K₅H(CN₂)₃ contains K⁺ and CN₂^2–, the anions exhibit D_∞h symmetry. According to ¹H and ¹³C solid state MAS-NMR investigations, temperature dependent impedance spectroscopy, and FTIR spectroscopy the protons are only loosely bound to the CN₂^2– ions. The proton conductivity shows a sharp increase above 70 °C.