Über ternäre Oxocuprate. X. Zur Kenntnis von Ba2Cu3O4Cl2

About Ternary Oxocuprates. X. On Ba₂Cu₃O₄Cl₂ The preparation of Ba₂Cu₃O₄Cl₂ and results by single crystal X-ray methods are described (a = 5.517, c = 13.808 Å; Space group D–I4/mmm). A so far unknown arrangement of square coordinated Cu²⁺ was detected. The Cu²⁺/O^2?-squares are partly completed to a distorted octahedral coordination by two Cl^?.     

Zur Kenntnis von Ba10Fe8Pt2Cl2O25

About Ba₁₀Fe₈Pt₂Cl₂O₂₅ The crystal structure of Ba₁₀Fe₈Pt₂Cl₂O₂₅ has been solved by direct methods, using intensity data collected by means of an automatic diffractometer (MoKα). It crystallizes in the hexagonal space group D–P6₃/mmc: a = 5.8034(4) Å, c = 24.997(5) Å, Z = 1. Fe³⁺ ions occur in both octahedral and tetrahedral coordination. Two types of Ba²⁺ ions are formed, with ten and twelve neighbouring atoms. The structure consists of plane connected FeO₆ and PtO₆ octahedra which are connected by corner shared FeO₄ tetrahedra.     

Synthese und Kristallstruktur von Ba25Cu142+Cu43+Zn4O49

Synthesis and Crystal Structure of Ba₂₅Cu₁₄²⁺Cu₄³⁺Zn₄O₄₉ Single crystals of Ba₂₅Cu₁₄²⁺Cu₄³⁺Zn₄O₄₉ were prepared with solid state and flux reactions. X-ray investigations show tetragonal symmetry, space group D⁷_4th–P4/nmm, a = 18.2146, c = 9.3230 Å, Z = 2. The hitherto unknown structure type shows copper in square pyramids and planar polygones, connected to six member rings or Cu₅O₂₀ groups. Slightly bent Cu₅O₁₂ groups produced by edge connection of five CuO₄ polygones are connected with ZnO₄ tetrahedra forming Cu₅Zn₄O₂₀ units. The complicated structure is shown step by step.     

Zur Kristallstruktur von Ba3In2O6

About the Crystal Structure of Ba₃In₂O₆ Single crystals of Ba₃In₂O₆ could be prepared by recrystallization of a flux and by solid state reaction in closed platinium tubes, respectively. Ba₃In₂O₆ crystallizes with tetragonal symmetry (space group 14/mmm, a = 4.1868; c = 21.7041 Å, Z = 2). Single crystal X-ray work lead to a crystal structure like La_2-xSr_1+xCu₂O_6-δ therefor Ba₃In₂O₆ is a modified member of the Sr₃Ti₂O₇-Type. The coordinations of Ba²⁺ and In³⁺ are described and the relations to the Sr₃Ti₂O₇-type are discussed.     

Ein neuer Bautyp der Oxohalogenoferrate: Ba3 Fe2 O5 Cl2 und Ba3 Fe2 O5 Br2

New Structure Type of the Two Oxohalogenoferrites: Ba₃Fe₂O₅Cl₂ and Ba₃Fe₂O₅Br₂ The hitherto unknown compounds Ba₃Fe₂O₅Cl₂ (A) and Ba₃Fe₂O₅Br₂ (B) are pre-pared and examined by single crystal techniques. (A) and (B) crystallizes in the cubic space group I2₁ 3-T⁵; (A) a = 9.9705(3) and (B) a = 10.0039(8) Å, Z = 4. The new structure consists of 10 corner-shared tetrahedra which are connected to a two-dimensional ring system. The differences to the previously investigated compound Sr₃Fe₂O₅Cl₂ are discussed.     

über Erdalkalimetalloxocuprate,VIII Zur Kenntnis von Sr2CuO2Cl2

On Alkaline Earth Oxocuprates VIII. About Sr₂CuO₂Cl₂ Sr₂CuO₂Cl₂ was prepared and investigated by single crystal X – ray work (space group D–Immm, a = 3.975, c = 15.618 Å). Sr₂CuO₂Cl₂ is isotypic with K₂NiF₄ – compounds and shows an octahedral configuration for Cu²⁺. Cl^? occupies trans-positions of the octahedral Cu²⁺/O^2? polyhedron. A discussion with related compounds (Sr₂CuO₃ and Nd₂CuO₄) explains the observed distribution of O^2? and Cl^?.     

Die Kristallstrukturen der hexagonalen Elpasolithe Ba3NiSb2O9 und Ba3CuSb2O9 – röntgenographische und spektroskopische Ergebnisse

The Structures of the Hexagonal Elpasolite-Type Compounds Ba₃NiSb₂O₉ and Ba₃CuSb₂O₉ The results of an X-ray single crystal study of the hexagonal elpasolite Ba(NiSb₂)⁽⁶⁾O₉ are given. (Space group: C; a = b = 5.837 Å, c = 14.392 Å; Z = 2). The structure can be described by close-packed BaO₃ layers alternating in the sequence c c h c c h … (hex. BaTiO₃ type). Groups of two octahedra with common faces are connected by SbO₆ octahedra via common corners. They are occupied alternately by Ni and Sb. The final reliability index was R = 3.0%. The Cu²⁺-compound is of the same structural type. The ligand field and EPR spectra are discussed in comparison with related Ni²⁺ and Cu²⁺ compounds.     

Ba2Cu3O5+δ as an intermediate phase during the synthesis of YBa2Cu4O8

We propose a reaction model for the synthesis of YBa₂Cu₄O₈ under normal pressure conditions, which contains 4 partial reaction steps. In a first step bariumnitrate and copperoxide react to Ba₂Cu₃O_5+δ. This substance will be formed for each mixtures Ba:Cu=2∶3...3∶2. The following two partial reaction steps are connected to Ba₂Cu₃O_5+δ, which reacts with Y₂O₃ and CuO to YBa₂Cu₄O₈ or decomposes to BaCuO₂ and CuO. In a last step parts of BaCuO₂ reacts with Y₂O₃ and CuO to YBa₂Cu₄O₈.     

Ba3Li2V2O7Cl4, a new vanadate with a channel structure

The tribarium dilithium divanadate tetrachloride Ba₃Li₂V₂O₇Cl₄ is a new vanadate with a channel structure and the first known vanadate containing both Ba and Li atoms. The structure contains four non‐equivalent Ba²⁺ sites (two with m and two with 2/m site symmetry), two Li⁺ sites, two nonmagnetic V⁵⁺ sites, five O²⁻ sites (three with m site symmetry) and four Cl⁻ sites (m site symmetry). One type of Li atom lies in LiO₄ tetrahedra (m site symmetry) and shares corners with VO₄ tetrahedra to form eight‐tetrahedron Li₃V₅O₂₄ rings and six‐tetrahedron Li₂V₄O₁₈ rings; these rings are linked within porous layers parallel to the ab plane and contain Ba²⁺ and Cl⁻ ions. The other Li atoms are located on inversion centres and form isolated chains of face‐sharing LiCl₆ octahedra.     

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].     

A series of oxygen-defect perovskites containing CuII and CuIII: The oxides La3−xLnxBa3 [CuII5−2y CuIII1+2y] O14+y

A series of oxygen-defect perovskites, containing Cu^II and Cu^III, La₃Ba₃ [Cu^II_5?2y Cu^III_1+2y] O_14+y, has been synthesized at 1000°C, for 0.05 ≤ y ≤ 0.43. The substitution of lanthanum for yttrium and lanthanides has been studied. These oxides are tetragonal: $\text{a = a}{}_{\mathrm{<mtext>p</mtext>}}\text{2}{}^{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ and c = 3a_p. The structural study of La₃Ba₃ Cu₆O_14.10 shows that oxygen vacancies are ordered, involving for copper three sorts of coordination: square, pyramidal (4 + 1), and distorted octahedral (4 + 2). The distribution of Cu^III, as well as the lanthanide ions on the different sites, is discussed.     

Über Oxocuprate. XIX. Ein Oxohalogenocuprat(I): Ba2CuO2Cl

On Oxocuprates. XIX. The Oxohalogenocuprate(I): Ba₂CuO₂Cl The hitherto unknown compound Ba₂CuO₂Cl was prepared and examined by single crystal X-ray diffractometer investigation (a = 983.5 pm, α = 25,04°; Space group D⁵_3d? R3 m). Cu⁺ has the coordination O? Cu? O, Ba²⁺ an octahedral surrounding. A discussion of the structure is given.     

Bis(N‐acetyltriethylphosphaniminium)‐tetraacetato‐dichloro‐dicuprat(II), [MeC(O)N(H)PEt3]2[Cu2(O2C–Me)4Cl2]

Bis(N‐acetyltriethylphosphaneiminium)‐tetraacetato‐dichloro‐dicuprate(II), [MeC(O)N(H)PEt₃]₂[Cu₂(O₂C–Me)₄Cl₂] The title compound has been prepared by the reaction of Me₃SiNPEt₃ with [Cu₂(O₂C–Me)₄] and MeC(O)Cl in dichloromethane solution to give colourless crystals which include four molecules CH₂Cl₂ per formula unit. The complex is characterized by IR spectroscopy and by a crystal structure determination. [MeC(O)N(H)PEt₃]₂[Cu₂(O₂C–Me)₄Cl₂] · 4 CH₂Cl₂: Space group P2₁/n, Z = 2, lattice dimensions at –70 °C: a = 794.1(1), b = 2356.9(6), c = 1327.3(2) pm; β = 91.00(1)°; R₁ = 0.0597. The structure consists of N‐acetyltriethylphosphaneiminium cations and dianions [Cu₂(O₂C–Me)₄Cl₂]^2– which form an iontriple with N–H…Cl hydrogen bridges.     

Zur Kristallchemie der Oxoplatinate

On the Crystal Chemistry of Oxoplatinates Referring to the coordination of Pt²⁺ and Pt⁴⁺ by oxygen the crystal structures of oxoplatinates will be systemized. Pt²⁺ exclusively shows in solids a square and planar coordination well known and typical for Cu²⁺, Pd²⁺ and Ni²⁺ too. Often mixed valences (Pt²⁺/Pt⁴⁺) are observed in square planar oxygen surrounding. Some exceptionally rare coordination is the dumbbell like O—Pt²⁺—O. The crystal chemistry of Pt⁴⁺ resembles the countless metal ions showing octahedral coordination by oxygen. Despite different compositions the compounds BaLn₂PtO₅, Ba₃Cu₂Ln₂PtO₁₀, Ba₅Ln₈Zn₄O₂₁, Ba₁₃Ln₈Zn₄Pt₄O₃₇ and Ba₁₇Ln₁₆Zn₈Pt₄O₅₇ show amazing relationships of polyhedra connections. Additionally will be shown that Ba₄Sm₄Zn₃PtO₁₅ is isotypic to Ba₆Nd₂Al₄O₁₅ and Ba₄NaCu_{0, 5}Pt_{1, 5}O₈ to Ba₁₅Pt₆O₂₇. Oxoplatinates containing lone pair active elements show one side open polyhedra. The positions of the free (s²) electrons are calculated using the Coulomb terms of lattice energy.     

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.     

Ein neues Alkali-Erdalkalimetall-Kupfer-Oxovanadat: Kba3Ca4Cu3V7O28

A new Alkaline-Alkaline-Earth-Copper-Oxovanadate: Kba₃Ca₄Cu₃V₇O₂₈ . Single crystals of Kba₃Ca₄Cu₃V₇O₂₈ were prepared by solid state reactions below the melting point of the reaction mixture. It crystallizes with hexagonal symmetry, space group C?P6₃mc, a=11.160, c=12.428 Å, Z=2. Kba₃Ca₄Cu₃V₇O₂₈ represents a new structure type with special coordination polyhedra around Ba²⁺, trigonal prisms and octahedra around Ca²⁺ and Cu²⁺ inside square pyramids. The crystal structure will be shown and discussed.     

Das erste Alkali-Erdalkali-Oxocuprat(II,III): NaBa2Cu22+Cu3+O6

The first Alkaline Alkaline-Earth Oxocuprate (II, III): NaBa₂Cu₂²⁺Cu³⁺O₆ The compound NaBa₂Cu₃O₆ was prepared by heating of Na₂O₂, BaO₂, Cu₂O in closed Ag-tubes. X-ray single crystal investigations led to orthorhombic symmetry, space group D-Fmmm; a = 8.4229; b = 11.4418; c = 14.4063 Å; Z = 8. Cu²⁺ and Cu³⁺ show square planar polygones of four and Na⁺ trigonal prisms of six O^2?. The two barium point positions show coordination numbers C.N. = 8 and 6 + 4. The crystal structure is discussed.     

Ein neues quaternäres Oxotitanat: Ba4Ti10Al2O27

A New Quaternary Oxotitanate: Ba₄Ti₁₀Al₂O₂₇ Single crystal of Ba₄Ti₁₀Al₂O₂₇ were prepared by heating oxide mixtures with NaOH flux for 20 days to 1300°C. X-ray investigations show monoclinic symmetry: a = 1973.7; b = 1134.9; c = 983.7 pm; β = 109.4°; space group C_2h³—C2/m. Ti⁴⁺/Al³⁺ occupy statistically more or less distorted octahedra, Ba²⁺ has an coordination number of 11 or 12, respectively. The complex frame work of octahedra is discussed.     

Guest-host copper(I, II) complex Rb11[Cul(H2O)2][Cul 15 1 Cl24(CuIICl6)]. effect of the nature of the [Cu 2 1 (H2O)2]2+ guest on crystal structure formation

The crystals of {Rb₁₁[Cu ₂ ¹ ( H₂O)₂]}[Cu ₁₅ ¹ Cl₂₄(Cu^IICl₆)] (I) formed in the RbCl-CuCl-H₂O -( O₂, C₂H₂ ) system were studied by X-ray diffraction analysis and ESR spectroscopy. The cell is monoclinic, space group B2/m, Z = 2, a = 24.787(3), b = 13.126(2), c = 11.318(5) Å, γ = 122.36(1)? (DARCH automatic diffractometer, γ(MoKgα). The crystal structure of compound I is a guest-host type structure consisting of the {[Cu ₁₅ ¹ Cl₂₄Cu₁₁Cl₆]^13?}n anion layers oriented perpendicularly to the [010] direction and containing large octahedral cavities (edge length =12 Å) with a discrete [ Cu^IICl₆ ] octahedron lying inside the cavity. The Rb⁺ cations and the charged [Cu ₂ ¹ ( H₂O)₂]²⁺ guest species lie between the anion layers. The effect of the nature of the guest on host structure formation is considered using compounds I and Rb₁₁[Cu ₁₅ ¹ Cl₁₆Brd₆Cu^IICl₆ ) Cu-C=CH] as examples.     

Determination of Cu3+, Bi5+ and Pb4+ in high Tc superconducting oxides by Cl2 generation, or by O2 together with Cl2 generation

Summary For estimating the values corresponding to the oxygen defects in high T_c superconducting oxides, iodometry has been applied for the determination of Cu³⁺ and Cu²⁺. The presence of Bi or Pb causes some difficulty in the identification of the end point of this titration, because of the formation of iodine complexes. Therefore, chlorine generation from HCl and iodometry was applied for the determination of Bi⁵⁺ or Pb⁴⁺ in the oxides, and for the additional determination of Cu³⁺, O₂ generation was used together with Cl₂ generation for Bi⁵⁺ or Pb⁴⁺.