Einbau von Al3+ in Ir3O12-Oktaedertripel in Ba4Ir2AlO10

Incorporation of Al³⁺ in Ir₃O₁₂ Octahedra-Triple in Ba₄Ir₂AlO₁₀ Single crystals of Ba₄Ir₂AlO₁₀ were prepared by solid state/flux reactions. It crystallizes with orthorhombic symmetry: space group D–Cmca; a = 5.778; b = 13.352; c = 13.084 Å; Z = 4. The structure is characterized by face connection of three IrO₆- or Ir/AlO₆-octahedra. X-ray investigations show an ordered occupation of the centric octahedron by Ir and a statistically distribution of Ir and Al in the adjacent octahedra. Calculations of the coulomb term of the lattice energy support a charge distribution in the manner Ir⁵⁺/Al³⁺? Ir⁴⁺? Ir⁵⁺/Al³⁺.     

Synthese und Struktur von Ba10[Ti4N12], ein ternäres Nitrid mit vierkernigen cyclischen Nitridotitanat-Ionen

Synthesis and Structure of Ba₁₀[Ti₄N₁₂], a Ternary Nitride with Tetranuclear Cyclic Nitridotitanate Ions Ba₁₀[Ti₄N₁₂] results from the reaction of Ba₃N₂, TiN, and N₂ at 980°C. It crystallizes in the triclinic space group P1 with the lattice parameters a = 644.3(4); b = 942.9(7); c = 966.9(7) pm, α = 106.37(4)°; β = 102.22(4)°; γ = 108.56(4)°, Z = 1. The crystal structure is built up by Ba²⁺ cations and tetranuclear cyclic nitridotitanate(IV) anions. In the anions four TiN₄ tetrahedra are each connected by two corners to form centrosymmetrical rings, which are stacked along [100] forming tubes. The Ti? N distances range from 192 to 199 pm.     

Zur Kenntnis von Ba6La2Co4O15

About Ba₆La₂Co₄O₁₅ Ba₆La₂Co₄O₁₅ were prepared and investigated by X-ray single crystal work. It crystallizes with hexagonal symmetry, space group C–P6₃mc; a = 11.8082; c = 7.0019 Å; Z = 2. Ba²⁺ show face connected BaO₆-octahedra and larger polyhedra of C.N. = 10 and 12. Co³⁺ is surrounded by four and six (tetrahedra, octahedra) oxygen. The Ba²⁺ and La³⁺ ions occupy one point position statistically.     

Ba5[CrN4]N: Das erste Nitridochromat(V)

Ba₅[CrN₄]N: The First Nitridochromate(V) Ba₅[CrN₄]N is prepared by reaction of mixtures of Li₃N, Ba₃N₂ and CrN/Cr₂N (1 : 1) (molar ratio Li : Ba : Cr = 3 : 5 : 1) in tantalum crucibles at 700°C with flowing nitrogen (1 atm) within a period of 48 h. After cooling down to room temperature (60°C/h) black-shining single crystals of the ternary phase with a platy habit are obtained (monoclinic, C2/m; a = 1054.0(2) pm, b = 1170.9(3) pm, c = 937.7(2) pm, b? = 110,79(2)°; Z = 4). The crystal structure contains isolated complex anions [Cr^VN₄]^7? which nearly satisfy the ideal tetrahedral symmetry (Cr? N [pm]: 2 × 175.3(4), 2 × 175.8(5); N? Cr? N [°]: 106.8(2), 109.5(2), 2 × 109.9(2), 2 × 110,3(2)). The coordination sphere for each of the terminal nitride functions of the complex anions is completed by five neighbouring Ba²⁺ ions (distorted CrBa₅ octahedra). The octahedra are connected via common CrBa₂ faces as well as CrBa edges thereby forming condensed tetrameric octahedral groups. The isolated nitride ions which are also present in the crystal structure of Ba₅[CrN₄]N are in an octahedral environment of Ba²⁺ ions. The presence of a d¹-System (Cr(V)) is confirmed by magnetic susceptibility data.     

Zur Kenntnis von Ba4Ir3O10

About Ba₄Ir₃O₁₀ Single crystals of Ba₄Ir₃O₁₀ were prepared by a flux technique. X-ray investigations show monoclinic symmetry, space group C_2h⁵–P2₁/a; a = 5.788; b = 13.222; c = 7.242 Å; β = 112.98°; Z = 2. Ir₃O₁₂ tripel, built up by face-sharing of IrO₆ octahedra, are edge-connected into wave-like twodimensional planes. Ba₄Ir₃O₁₀ is related to Ba₄(Ti, Pt)₃O₁₀.     

Nd4Ti9O24: Präparation und Struktur

Preparation and Crystal Structure of Nd₄Ti₉O₂₄ The compound Nd₄Ti₉O₂₄ was prepared by heating mixtures of Nd₂O₃/TiO₂ (1 : 4.5) at temperatures of T = 1 330°C in air (2× 1d). Single crystals of Nd₄Ti₉O₂₄ were obtained by chemical transport reaction (T₂→T₁; T₁ = 1000°C, T₁ = 900°C, 14 d) using chlorine (p(Cl₂, 298 K) = 1 atm) as transport agent with Nd₄Ti₉O₂₄ as starting material. Nd₄Ti₉O₂₄ crystallizes in the orthorhombic space group Fddd (No. 70) with a = 13.9926(11) Å, b = 35.2844(21) Å, c = 14.4676(17) Å (Z = 16). The structure was refined to give R = 4.0% and R, = 3.7%. Main building units are TiO₆ octahedra, NdO₆ distorted square antiprisms and NdO₆ octahedra.     

Geordnete Oktaederbesetzung in Ba6La2Al1,5Fe2,5O15

Ordered Occupation of Octahedra in Ba₆La₂Al_1,5Fe_2,5O₁₅ Ba₆La₂Al_1.5Fe_2.5O₁₅ was prepared and investigated by X-ray single crystal technique. It crystallizes in the space group C – P6₃mc; a = 11.814, c = 7.1003 Å; Z = 2. The M³⁺O₆ octahedra are occupied exclusively by Fe³⁺ ions, the M³⁺O₄ tetrahedra in contrast are statistically filled by Fe³⁺ and Al³⁺ ions. Ba₆La₂Al_1.5Fe_2.5O₁₅ is a partially ordered mixed crystal of the pure iron and aluminium compounds.     

Synthese und Kristallstruktur von Ba6ZnIn2Cl20

Synthesis and Crystal Structure of Ba₆ZnIn₂Cl₂₀ Colourless single crystals of Ba₆ZnIn₂Cl₂₀ are obtained from a 6 : 3 : 2 molar mixture of BaCl₂, ZnCl₂ and InCl₃ at 420 °C in a Pyrex ampoule. It crystallizes with the monoclinic space group P2₁/c (Z = 4) with a = 1957.8(2), b = 1014.69(8), c = 1778.7(2) pm, β = 110.94(1)°, in a new structure. Zn²⁺ is surrounded tetrahedrally and In³⁺ octahedrally by chloride ions. Half of the [InCl₆] octahedra are isolated from each other, the other half shares common edges to form [In₂Cl₁₀] double octahedra. Ba²⁺ has coordination numbers of eight and nine. There are chloride ions that do not belong to Zn²⁺ or In³⁺ so that the formula may be written as Ba₁₂Cl₁₀[ZnCl₄]₂[InCl₆]₂[In₂Cl₁₀].     

Synthese und Kristallstruktur von Ba6Lu4Zn10O22 mit [OBa6]-Oktaedern

On the Synthesis and Crystal Structure of Ba₆Lu₄Zn₁₀O₂₂ with [OBa₆] Octahedra Single crystals of Ba₆Lu₄Zn₁₀O₂₂ have been prepared by high temperature reactions and investigated by X-ray techniques. This compound is isotypic to Ba₃In₂Zn₅O₁₁ and the first member of the Rare Earth elements. Ba₆Lu₄Zn₁₀O₂₂ crystallizes with cubic symmetry, space group T-F4 3m, a = 13.452(1) Å and Z = 4. Zn²⁺ shows a tetrahedral, Lu³⁺ an octahedral and Ba²⁺ a three-fold capped trigonal prismatic coordination by O^2?. The ZnO₄ tetrahedra and LuO₆ octahedra are forming macro polyhedra of the type Zn₁₀O₂₀ and Lu₄O₁₆. A discussion is given for the Ba₆O₃₃ and Ba₆O₄₂ groups.     

Zur Kenntnis eines Halogenooxo-Cobaltats(III): Sr8Co6O15Cl4

On an Oxide Chloride of Co^III: Sr₈Co₆O₁₅Cl₄ Sr₈Co₆O₁₅Cl₄ was prepared for the first time by flux reaction. It crystallizes with tetragonal symmetry: space group D_4h¹⁷–I4/mmm; a = 3.927; c = 31.429 Å; Z = 1. Co³⁺ has different coordinations. One point position show CoO₆ octahedra, the other one has a CoO₅Cl surrounding. An oxygen deficit exhibit partly distorted square pyramids. Sr₈Co₆O₁₅Cl₄ is strongly related to Ba₈In₆O_17.5 or can be seen as Sr₄Co₃O_7.5Cl₂ as a variety of the Sr₄Ti₃O₁₀ type.     

The crystal structure of a complex barium,aluminium, copper(II) fluoride: Ba4Cu2Al3F21

Ba₄Cu₂Al₃F₂₁ is orthorhombic : a = 5.299(1) Å, b = 7.318(1) Å, c = 41.529(7) Å, Z = 4. The crystal structure was solved in the space group P2₁2₁2₁ (n^o19) from X-ray single crystal data using 5682 unique reflections (3698 with F_O/σ(F) > 4). It consists in a succession along c of 8 layers of 2 different types of sheets. The first layer, formulated [Cu₂AlF₁₁]⁴⁻ in which copper-fluorine octahedra are linked by edges to form infinite distorted chains connected together by aluminium-fluorine octahedra, is followed by two [Al₂F₁₀]⁴⁻ layers of infinite cischains of aluminium-fluorine octahedra linked by two vertices and another [Cu₂AlF₁₁]⁴⁻ layer. These 4 layers are doubled along c by one of the screw-axes 2₁. The barium ions, 12-coordinated, are inserted between the sheets.     

SmAlF5 — ein neues SmII-fluoroaluminat mit Al2F10-Oktaederdoppeln und [AlF2/2F4/1]-Ketten

SmAlF₅ — a New Samarium(II) Fluoroaluminate with Al₂F₁₀ Bioctahedra and [AlF_2/2F_4/1] Chains . SmAlF₅ has been obtained as orange-red transparent single crystals while heating mixtures of SmF₃, Sm-powder and AlF₃ (2:1:3) in a niobium crucible under Ar after 7?10 d at about 750°C. SmAlF₅ crystallises in I 4/m (Nr. 87) with a=1 414.4(4), c=722.2(3) pm and Z=8 (CAD4, 4 340 I_O, R_w=1.7%). The crystal structure of SmAlF₅ is isotypic to BaTiF₅. Characteristic building units are linear chains of trans-corner sharing AlF₆ octahedra, which are connected via corners to two further AlF₆ octahedra. Isolated Al₂F₁₀ octahedra lie disordered between such chains. The Sm atoms connect the AlF₆ octahedra to a three-dimensional network. Measurements of the magnetic susceptibility show the temperature dependence typically found for Sm²⁺. The Madelung part of the lattice energy has been calculated and is discussed.     

Ba3V2O4F8: [V4(O,F)20]8− tetrameric groups of octahedra inserted a tridimensional network of (FBa4) tetrahedra

Ba₃V₂O₄F₈ is prepared by hydrothermal synthesis. The crystal structure is established from single crystal X-ray diffraction data: Space group Pnnm, Z = 4, a = 9.945(4) Å, b = 10.277(1) Å and c = 9.673(1) Å R = 0.0331, R_w = 0.0315 for 892 independent reflections and 86 parameters. The structure is related to that Ba₃Al₂F₁₂ and is described in terms of isolated [V₄(O,F)₂₀]^8? tetrameric groups of octahedra inserted in a tridimensional network of (FBa₄) tetrahedra. Location of oxygen and fluorine atoms is discussed with the help of bond valence calculations.     

Mononuclear Thiolatecobalt Carbonyls

A Partial Statistically Incorporation of Ca²⁺ into the Ba₆Nd₂Al₄O₁₅-Type: Ba₅CaLa₂Fe₄O₁₅ Using high temperature reactions we succeeded in incorporating Ca²⁺ into the Ba₆Nd₂Al₄O₁₅ type. Single crystal X-ray methods reveal a partly ordered alkaline earth distribution. Ba²⁺ and Ca²⁺ occupy face connected MO₆-octahedra as well as a further point position together with La³⁺ ions (space group C−P6₃mc; a = 11.770; c = 7.039 Å; Z = 2).     

Darstellung der freien Dodekawolframatoaluminiumsäure H5[AlO4W12O36] · 6 H2O mittels Gefriertrocknung

Preparation of the Free 12-Tungstoaluminium Acid H₅[AlO₄W₁₂O₃₆] · 6 H₂O by Means of the Cryogenic Method The title compound was first prepared in solid state from its aqueous solution by means of the cryogenic method and characterized by chemical and thermal analyses, IR and UV spectroscopy. From X-ray heating patterns the formation of a new cubic phase 1/2 Al₂O₃ · 12 WO₃ (I) at 400°C was found, being stable till 830°C: a = 378 pm (600°C). High-resolution ²⁷Al NMR (MAS-technique) was used to determine the tetrahedral coordination of aluminium in the title compound and the octahedral coordination in I. The degradation of the doped WO₃-phase I into Al₂(WO₄)₃ begins at 600°C. Above 830°C tetragonal WO₃ and Al₂(WO₄)₃ coexist.     

Ein Beitrag über Ba3Pt4HgO11: Das erste Erdkalimetall-Oxoplatinat(II,V)/Oxomercurat

A Contribution on Ba₃Pt₄HgO₁₁: The First Alkaline-Earth Oxoplatinate(II,V)/Oxomercurate Single crystals of Ba₃Pt₄HgO₁₁ were prepared by oxygen high pressure technique (4 200–3 600 bar) and investigated by X-ray methods. It crystallizes with hexagonal symmetry, space group D? P6 2c, a = 6.021, c = 17.374 Å, Z = 2. Ba₃Pt₄HgO₁₁ represents a new structure type, showing structural relationships to Ba₂Hg₃Pd₇O₁₄ and to the precious metal 6L-perovskites. The Hg²⁺ ions show dumb-bell like coordination, Pt²⁺ a square-planar surrounding and Pt⁵⁺ face shared double octahedra.     

Über hexagonale Perowskite mit Kationenfehlstellen. XXVII. Die Systeme Ba4−xSrxBIIRe2□O12′, Ba4BCaxRe2□O12 und Ba4−xLaxBIIRe2−xWx□O12 mit BII = Co,Ni

On Hexagonal Perovskites with Cationic Vacancies. XXVII. Systems Ba_4?xSr_xB^IIRe₂□O₁₂, Ba₄B Ca_xRe₂□O₁₂, and Ba_4?xLa_xB^IIRe_2?xW_x□O₁₂ with B^II = Co, Ni In the systems Ba_4?xSr_xB^IIRe₂□O₁₂, Ba₄BCa_xRe₂□O₁₂ and Ba_4?xLa_xB^IIRe_2?xW_x□O₁₂ (B^II = Co, Ni) hexagonal perovskites with a rhombohedral 12 L structure (general composition A₄BM₂□O₁₂; sequence (hhcc)₃; space group R&3macr;m) are observed. With the exception of Ba₄NiRe₂□O₁₂ the octahedral net consists of BO₆ single octahedra and M₂□O₁₂ face connected blocks (type 1). In type 2 (Ba₄NiRe₂□O₁₂) the M ions are located in the single octahedra and in the center of the groups of three face connected octahedra. The two outer positions of the latter are occupied by B ions and vacancies in the ratio 1:1. The difference between type 1 and 2 are discussed by means of the vibrational and diffuse reflectance spectra.     

Chemical and structural transformations in manganese aluminum spinel of the composition Mn1.5Al1.5O4 during heating and cooling in air

Single phase cubic spinel of the composition Mn_1.5Al_1.5O₄ is synthesized. Its crystal structure refinement shows that 0.4Mn+0.6Al are in the octahedral sites and 0.7Mn+0.3Al are in the tetrahedral sites. High temperature X-ray diffraction is used to analyze Mn_1.5Al_1.5O₄ behavior during heating and cooling in air. In a temperature range of 600°C to 700°C, initial spinel splits into layers, and the sample represents a twophase system: cubic spinel Mn_0.4Al_2.4O₄ and a phase based on β-Mn₃O₄. Above 900°C the sample again turns into single phase cubic spinel. The role of oxidizing processes in the decomposition of Mn_1.5Al_1.5O₄ caused by oxygenation and partial oxidation of Mn²⁺ to Mn³⁺ is shown. A scheme of structural transformations of manganese aluminum spinel during heating from room temperature and cooling from 950°C is proposed.     

Über Oxotitanate der Alkalimetalle. Zur Kenntnis von Na4Ti5O12

On Oxotitanates of the Alkaline Metals: On Na₄Ti₅O₁₂ Colourless single crystals of the new titanate Na₄Ti₅O₁₂ (starting from mixtures Na₂O/TiO₂, 1000°C, 6 d, Au-crucible, open system) crystallize in the monoclinic system, space group C2/m, a = 26.544(9), b = 2.952(1), c = 6.322(3) Å, β = 95.79(3)°, Z = 2, d_rö = 3.45 and d_pyk = 3.38 g · cm^?3 (four-cycle-diffractometer data, PW 1100, 2?-scan, MoKα). R = 5.09% and R_w = 4.87% for 1178 independent I₀(hkl) with 3° ≤ 2? ≤ 34°. Corrugated layers of Ti₅O₁₂, held together by Na⁺, are stacked along [001]. Details about partially occupied positions of Na⁺, Effective Coordination Numbers (ECoN), the Madelung part of lattice energy (MAPLE), and the structural differences to Na₂Ti₃O₇ are discussed.     

Zur Konstitution von Ba2WO3F4 und Ba2MoO3F4

On the Structure of Ba₂Wo₃F₄ and Ba₂MoO₃F₄ Ba₂[WO_2/2O₂F₂]F₂ has been prepared for the first time as colourless single crystals (from powder, Au-tube, 680°C, 90 d). It crystallizes in the monoclinic (C c) crystal system with a = 1151.1, b = 938.2, c = 718.8 pm, ß = 126.17°, Z = 4. d_x = 6.17, d_pyk = 6.13 g · cm^?3. (Fourcirclediffractometer PW 1100, Fa. Philips, MoKα-, ω-2Θ-scan, 1832 I₀(hkl) R = 8.3, R_w = 7.4%). Parameters see in the text. The isotypic Ba₂MoO₃F₄ has been prepared as powder (a = 1147.5, b = 937.0, c = 725.1 pm, ß = 126.42°). The structure shows chains of (WO_2/2O₂F₂) groups along [001]. To establish O^2? and F^? on the positions IR and Raman Spectra are employed. The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed.