Cobalthydrogenarsenat-Monohydrat. Darstellung und Kristallstruktur

Cobalt(II) Hydrogenarsenate Monohydrate. Preparation and Crystal Structure Co[H₂O|HOAsO₃] was prepared by heating of As₂O₅, CoSO₄ · 7 H₂O and H₂O at 150°C in a sealed tube and investigated by X-rays. The compound crystallizes triclinic, space group P¯1 with a = 786.5, b = 1569.9, c = 671.9 pm, α = 94.25, β = 96.89, γ = 90.28° and Z = 8. The structure contains chains of edge-shared CoO₆ octahedra connected by AsO₄ tetrahedra forming sheets. Two of such somewhat different sheets built up the whole structure. Based on the charge balance derived from the geometrical data and the IR spectra the occurrence of hydrogen bridges is discussed.     

Tetramethylammonium-calcium-triazid. Darstellung und Kristallstruktur

[N(CH₃)₄]Ca(N₃)₃,M=240.29, was prepared from aqueous solutions of tetramethylammoniumazide with calciumazide at 298 K. The crystals are tetragonala=936.6(7) pm,c=694.7(5)pm, space group P4/nmm,Z=2, (x)=1.31Mgm^–3. The crystal structure was determined by single crystal x-ray diffraction (234 Mo-K-reflections, =0.469 mm^–1,R=0.064). Calcium is octahedrally coordinated to six azide groups. The octahedra are connected via azide groups to a threedimensional array with the complex ammonium ions between. The terminal nitrogen atoms of the azide groups and the methyl groups are considerably disordered.

     

Darstellung und Kristallstruktur von KSbS2

Preparation and Crystal Structure of KSbS₂ Red KSbS₂ was prepared in a aqueous solution of KHS and Sb₂S₃ under mild hydrothermal conditions. For crystallographic data see ?Inhaltsübersicht”?. There are SbS-chains, built up by ψ-trigonal bipyramids, which are connected by sharing edges. The K⁺-Ions between these chains have a nearly octaedric coordination.     

Darstellung und Kristallstruktur von CsBO2

Preparation and Crystal Structure of CsBO₂ Colourless single crystals of CsBO₂ have been prepared from intimate mixtures of CsO_0.57 and B₂O₃ (Cs:B = 3.2:1.0; 600°C, 38 d). The structure determination from fourcircle diffractometer data (MoK, 443 I_o (h k l), R = 3.1%, R_w = 2.0%) confirms the isotypy with NaBO₂ and KBO₂: space group R 3 c; a = 1 363.7(2) pm, c = 836.5(2) pm; Z = 18. A characteristic structure unit is the planar cyclic anion [B₃O₆]^3?. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR), the Madelung Part of Lattice Energy (MAPLE) and the Charge Distribution (CHARDI) are calculated and discussed.     

Darstellung und Kristallstruktur von SrCu2Sb2 und SrZnBi2

Preparation and Crystal Structure of SrCu₂Sb₂ and SrZnBi₂ SrCu₂Sb₂ and SrZnBi₂ have been prepared and analytically and structurally characterized. SrCu₂Sb₂ crystallizes tetragonal in the CaBe₂Ge₂ structure type. SrZnBi₂ has its own structure type. In both structures the transition metal atoms form with the semimetal atoms tetragonal pyramids, which are connected by common edges of the basis to twodimensional sheets. These sheets are separated in the case of SrCu₂Sb₂ by single sheets of strontium atoms, in the case of SrZnBi₂ by double sheets of strontium atoms in which fourfold nets of Bi atoms are located.     

Darstellung und Kristallstruktur von Ag2MnO4

Synthese and Crystal Structure of Ag₂MnO₄ Single crystals of Ag₂MnO₄ have been grown from aqueous solution. The crystal structure has been solved and refined using diffractometer data (Pnma, a = 999.8(2); b = 698.9(1); c = 547.4(2) pm). The mean bond-length Mn? O within the tetrahedral anions is 167.9 pm. In spite of similar lattice constants and identical space group, Ag₂MnO₄ is not isostructural to Olivine. The structural differences are discussed.     

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.     

Darstellung und Kristallstruktur von HfOS

Synthesis and Crystal Structure of HfOS On attempts to prepare binary and ternary hafnium sulfides a small quantity of single crystals was obtained which could be identified as HfOS. The new compound is cubic, space group P2₁3 with a = 5.6824(6) Å. It is isostructural with the cubic form o ZrOS. In order to refine the structure parameters intensity measurements were carried out by means of a four-circle single crystal diffractometer.     

Darstellung und Kristallstruktur von Cu2SrSnS4

Preparation and Crystal Structure of Cu₂SrSnS₄ Cu₂SrSnS₄ was prepared from a mixture of the three binary sulfides at 620-700° C. The structure analyses by single crystal X-ray investigations yields a trigonal C-symmetrie for the unit of the structure with a = 6.29₀ and c = 15.57₈ Å and three formula units. Space group: C–P3₁ (No. 144). Copper and tin have tetrahedral surrounding of S^2?. The neighbourhood of Sr²⁺ has the shape of a deformed archimedic antiprisma.     

Darstellung und Kristallstruktur von Ag2O3

Preparation and Crystal Structure of Ag₂O₃ The novel compound Ag₂O₃ was obtained by anodic oxidation of aqueous solutions of AgBF₄, AgClO₄, and AgPF₆. According to single crystal investigations Ag₂O₃ belongs to the orthorhombic crystal system (Fdd2; a = 1286.9(1), b = 1049.0(1), c = 366.38(5) pm; Z = 8; 309 independent diffractometer data; R = 1.2%). Ag₂O₃ is isostructural to Au₂O₃ and contains silver square-planarly coordinated by oxygen. The AgO₄ groups are connected via common vertices forming a 3-d framework.     

Zur Darstellung und Kristallstruktur von Tl2O

The preparation of Tl₂O and its crystal structure is discussed. By FOURIER methods for a monoclinic unit cell(a_M = 6.08₂, b_M = 3.52₀, c_M = 13.2₄ Å, β = 108.2°, Z = 4, space group C_2h³) the determined atomic parameters can be transformed into the trigonal system by the assumption of special oxygen positions (space group No. 166–R3 m). Correspondingly the Tl₂O crystal structure may be described as a threefold polytype form of the anti CdJ₂ type (a_H = 3,51₆ c_H = 37.8₄ Å; c/a = 10.76, Z = 6, mol. vol. = 40.7 cm³; d_x = 10.44, d_pyk = 10.4 g m^?).     

Darstellung und Kristallstruktur von CsSb2Se4

Preparation and Crystal Structure of CsSb₂Se₄ CsSb₂Se₄ was prepared by hydrothermal reaction of Cs₂CO₃ with Sb₂Se₃ at a temperature of 115°C. An X-ray structural analysis demonstrated that the compound contains polyselenoantimonate(III) anions (Sb₂Se₄^?)_n, which display both (Sb)Se? Sb and (Sb)Se? Se(Sb) bridges. A ψ-tetrahedral coordination is observed for one of the independent Sb atoms, a ψ-trigonal bipyramidal coordination for the other. The Sb? Se polyhedra are linked through joint corners and edges and in addition via direct Se? Se bonds into sheets.     

Darstellung und Kristallstruktur von Tl2PdCl4

Synthesis and Crystal Structure of Tl₂PdCl₄ Single crystals of Tl₂PdCl₄ can be obtained by hydrothermal synthesis [1, 2]. They show tetragonal symmetry with space group P4/mmm (No. 123). The lattice parameters are a = 7.163(1) Å and c = 4.282 (1) Å. The atomic arrangement of Tl₂PdCl₄ is explored by X‐ray crystal structure analysis. Tl₂PdCl₄ is isotypic with K₂PtCl₄.     

Darstellung und Kristallstruktur von Cs8P8O24 · 8H2O

Synthesis and Crystal Structure of Cs₈P₈O₂₄ · 8H₂O Cs₈P₈O₂₄ · 8H₂O was obtained from Na₈P₈O₂₄ · 6H₂O by cation exchange. Crystal growth was achieved by applying gel techniques (agar agar). The crystal structure (P1 ; a = 766.6(8); b = 1 156.9(9); c = 1 163.4(9) pm; α = 100,2(1)°; β = 106.5(2)°; γ = 92.2(1)°; Z = 1; 4 099 unique diffractometer data; R = 0.051; R(w) = 0.037) contains cyclo-octaphosphate anions with point symmetry C_2h. The cesium atoms are coordinated irregularily by eight and ten oxygen atoms, respectively. The threedimensional linkage of the P₈O₂₄^8?-rings is established via bonds to cesium atoms and hydrogen bonds Provided by H₂O molecules.     

Darstellung und Kristallstruktur von TICu[CuO2]

Investigations on Electronically Conducting Oxide Systems. XVI. Solid Solutions and Conductivity in the System MgTi₂O₅? Ti₃O₅ Solid solution formation is reported for the system Mg_1–xTi_2–x^IVTi_2x^IIIO₅. With increasing x there is at room temperature a transition from the orthorhombic pseudobrookite structure to the monoclinic low-temperature modification of Ti₃O₅. The X-ray diffraction pattern results are supported by DSC measurements, electrical and magnetic investigations. The tendency of Ti? Ti pair formation in the low-temperature Ti₃O₅ structure is accompanied by a drop of the activation energy for electrical conductivity and a decreasing susceptibility at high Ti^III concentrations.     

Darstellung und Kristallstruktur der Calciumnitridhalogenide Ca2NCl und Ca2NBr

Preparation and Crystal Structure of the Calcium Nitride Halides Ca₂NCl and Ca₂NBr Ca₂NCl and Ca₂NBr were prepared as well crystalline powders of light-grey colour by reaction of Ca₃N₂ and CaX₂ in a molar ratio 1:1 in steel ampoules under argon (50 h 740°C; 15 h 1 000°C and 40 h 950°C, resp.). Brownish transparent single crystals were obtained by annealing specimens in molybdenum ampoules (25 d 1 125°C). The compounds crystallize in the anti-α-NaFeO₂-structure (Crystallographic data: see “Inhaltsübersicht”). N^3? and X^? are rhombohedrally distorted cubic close packed. The sequence of the anionic layers is X^?? N^3?? X^?? N^3?? …?. Ca²⁺ is shifted towards N^3? so that Ca₂N⁺ layers are formed which are held together by the halide ions.     

Darstellung,Kristallstruktur und Eigenschaften von KLi2As

Preparation, Crystal Structure, and Properties of KLi₂As The novel arsenide KLi₂As has been synthesized either from the elements or from mixtures of the binary components Li₃As and K₃As in sealed Nb ampoules at 823 K and 623 K, respectively. It crystallizes in the space group Pmmn (no. 59) with a = 445.8(9); b = 671.5(11); c = 627.0(12) pm and Z = 2 formula units. The metallic reflecting silvercoloured platelets hydrolize rapidly under wet air. The compound (Pearson code oP8) is isopuntal with BaLi₂Si and an intermediate between the Li₃N and the Na₃As type of structure. Potassium is distorted tetrahedrally coordinated by four As atoms (d(K? As) = 355 and 367 pm), arsenic by four potassium and six lithium atoms (d(As? K) = 355–367 pm; d(As? Li) = 260–265 pm) in form of a sphenocorona. Lithium is threefold coordinated (distorted trigonal planar) by arsenic and this unit is enveloped by a monocapped trigonal prism build by three lithium and four potassium atoms.     

Darstellung und Kristallstruktur von CsTe4

Preparation and Crystal Structure of CsTe₄ CsTe₄ results from a melting reaction at 570°C in sealed quartztubes. The starting materials Cs and Te in the molar ratio 1:4 are produced in a first step by controlled decomposition of the CsN₃ from mixtures of CsN₃ and Te (1:4) at 350°C. CsTe₄ is monoclinic, space group P2₁/c, with a = 7.857(1) Å, b = 7.286(1) Å, c = 14.155(2) Å, β = 93.83(1)°, and Z = 4. The tellurium atoms form a two-dimensional puckered layer built of from pseudo-trigonal-bipyramidal, T-shaped units Te₄^?. The central tellurium atom of this unit may be considered as a pseudo iodine. The compound is compared with other tellurides MTe_n having some like that unexpected principles of connection.     

Niobpentachlorid-Thiazylchlorid-Addukt Darstellung,Schwingungsspektrum und Kristallstruktur

Complex of Niobium Pentachloride with Thiazyl Chloride Preparation, Vibrational Spectrum, and Crystal Structure Niobium pentachloride reacts with trithiazylchloride in CCl₄-suspension forming the complex Cl₅Nb? NSCl which forms red crystals that are very sensitive to moisture. According to the vibrational spectrum and the crystal structure determination the compound consists of monomeric units in which NbCl₅ is bonded to N?S? Cl in a relatively loose manner via the nitrogen atom. The crystal structure was determined with X-ray diffraction data and was refined to a residual index of R = 0.019 for 1879 reflexions. Cl₅NbNSCl crystallizes in the triclinic space group P1 with the lattice constants a = 636.7, b = 1215.5, c = 1266.8 pm, α = 83.32, β = 78.52 und γ = 82.26° and with four molecules per unit cell. There are two crystallographically independent molecules which differ somewhat in their geometry.     

Darstellung,spektroskopische Untersuchungen und Kristallstruktur von [Cl4SbO2P(CH3)2]2

Preparation, Spectroscopic and Crystal Structure Investigations of [Cl₄SbO₂P(CH₃)₂]₂ [Cl₄SbO₂P(CH₃)₂]₂ was prepared from SbCl₅ and HOP(O)(CH₃)₂ in CH₂Cl₂. The compound crystallizes in the space group P2₁/n with two dimeric units per unit cell; the lattice constants are a = 875, b = 1306, c = 923 pm and β 97.1°. Structural investigation by X-ray diffraction methods showed the Sb atoms in the dimeric units to be linked by O? P? O-bridges of the dimethylphosphinate groups to Sb₂O₄P₂ eight-rings of approximate symmetry C_2h. The vibrational spectrum (i.r., Raman) and the n.m.r. spectra (³¹P, ¹H) consist with this structure.