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.     

Zur Kenntnis komplexer Fluoride mit Cu2+ und Pd2+: MPtF6 (M  Pd,Cu) und RbCuPdF5

On Complex Fluorides with Cu²⁺ and Pd²⁺: MPtF₆ (M ? Pd, Cu) and RbCuPdF₅ For the first time single crystals of PdPtF₆ (green), trigonal-rhomboedric, a = 503.8, c = 1431.6 pm, spcgr. R3 ? C (No. 148), Z = 3, CuPtF₆ (orange), triclinic, a = 495.2, b = 498.5, c = 962.4 pm, α = 89.98, β = 104.23, γ = 120.35°, spcgr. P1 ? C (No. 2), Z = 2 and RbCuPdF₅ (orange brown, in connection with investigations on M^IPd₂F₅ [1]), orthorhombic, a = 626.9, b = 719.9, c = 1076.3 pm, spcgr. Pnma? D (No. 62), Z = 4, four circle diffractometer data, have been obtained.     

Zur Atomverteilung in Ba2SrIn2O6 mit einem Beitrag zur Existenz des Calciumferrat(III)-Typs bei Oxoindaten

On the Atomic Distribution in Ba₂SrIn₂O₆ with a Contribution to the Existence of the Calciumferrite-Type of Oxoindates (I) Ba₂SrIn₂O₆ and (II) Sr_0.93Ba_0.07In₂O₄ were prepared and investigated by single crystal X-ray technique. I crystallizes with tetragonal symmetry, space group D – I4/mmm, a = 4.168; c = 21.290 Å; Z = 2; II belongs to the orthorhombic space group D – Pnma, a = 9.858; b = 3.273; c = 11.520 Å; Z = 4. I shows in respect to the formerly investigated compound BaSr₂In₂O₆ an unexpected statistically distribution of Ba²⁺ and Sr²⁺ with the La₂SrCu₂O₆ type. II marks the range of existence of the calciumferrite type within the alkaline earth oxoindates in direction of large radii of M²⁺ ions.     

Zur Kenntnis eines Erdalkalimetall-Oxopalladats(II) mit ringförmigen Pd6O12-Baugruppen: CaBa2Pd3O6

On an Alkaline-Earth Oxopalladate containing Pd₆O₁₂ Rings: CaBa₂Pd₃O₆ CaBa₂Pd₃O₆ was prepared for the first time and investigated by X-ray single crystal technique. It is isotypic to NaBa₂Cu₃O₆ and crystallizes with orthorhombic symmetry, space group D-Fmmm, a = 8.717, b = 11.47, c = 14.933 Å; Z = 2. Typical features of the crystal structure are edge connected square planar PdO₄ polygones, forming isolated Pd₆O₁₂ rings.     

Das erste Alkali-Erdalkalimetall-Oxoniccolat(II,III): NaBa2Ni22+Ni3+O6

The First Alkalinc Alkaline Earth Oxoniccolate(II,III): NaBa₂Ni₂²⁺Ni³⁺O₆ Single crystals of NaBa₂Ni₂²⁺Ni³⁺O₆ were prepared by solid state reaction. X-ray investigations led to orthorhombic symmetry, space group D-Fmmm; a = 8.310; b = 11.220; c = 14.397 Å; Z = 8. Na⁺ is coordinated by six O^2? in form of a trigonal prism and the two Ba²⁺ point positions show different coordination numbers C.N. = 6 + 4 and 8. The Ni²⁺ /Ni³⁺ ions are in square planar polygons, six of them are forming a so far unknown closed macro polyhedra.     

Ein neues Oxometallat mit Mangan(II): Ba5Mn4Nd8O21

On a New Oxometallate of Manganese (II): Ba₅Mn₄Nd₈O₂₁ Single crystals of Ba₅Mn₄Nd₈O₂₁ were prepared for the first time by CO₂-Laser technique using H₂-atmosphere. It was investigated by a single crystal X-ray diffractometer study. Ba₅Mn₄Nd₈O₂₁ crystallizes with tetragonal symmetry space group: C? I4/m; a = 14.2104 Å; c = 5.8581 Å; Z = 2. Mn²⁺ is found in square pyramids of oxygen.     

Zur Kristallchemie der Kupfer-Lanthanoid-Oxowolframate: (I) triklin-α-CuTbW2O8, (II) monoklin-CuInW2O8 und (III) monoklin-CuYW2O8

The Crystal Chemistry of Copper Rare-Earth Oxotungstates: (I): triclinic-α-CuTbW₂O₈, (II): monoclinic-CuInW₂O₈ and (III): monoclinic-CuYW₂O₈ Single crystals of (I), (II) and (III) were prepared by recrystallisation in closed systems and examined by X-ray technique. (I): space group C? P1 , a = 7.3080, b = 7.8945, c = 7.1476 Å, α = 115.23, β = 116.21, γ = 56.98°, Z = 2; (II): space group C? C2/c, a = 9.6576, b = 11.6496, c = 4.9863 Å, β = 91.17°, Z = 4; (III): space group C? P2/n, a = 10.0504, b = 5.8214, c = 5.0224 Å, β = 94.23°, Z = 2. The crystal structures are discussed with respect to calculations of the coulombterms of lattice energy and possible valence states of Cu²⁺ and Mo⁵⁺.     

Synthese und Struktur des ersten ternären Blei(II)-Oxocuprats(I): PbCu2O2

Synthesis and Structure of the First Ternary Lead(II) Copper(I) Oxide: PbCu₂O₂ PbCu₂O₂ can be prepared by solid state reaction or by precipitation from a basic aqueous solution. Single crystals of the new compound were prepared by recrystallisation from a molten mixture (PbO? Cu₂O) and investigated by X-ray diffractometer technique. PbCu₂O₂ crystallizes isotypically with the homologue silver compound PbAg₂O₂ (monoclinic with a = 8.22₃ Å, b = 8.28₉ Å, c = 6.01₅ Å, β = 132.6₂°, Z = 4, space group C? C 1 2/c 1). The crystallographic data from the X-ray investigation are reported. The structure is built by endless [PbO_4/4]- and [CuO_2/4]-chains. Pb²⁺ has a one-sided asymmetric coordination with four next oxygen neighbours and Cu⁺ forms a stretched dumbbell with two oxygen atoms.     

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.     

Neue Ternäre Silber(II)-fluoride: Ag3IIM2IVF14 (MIV = Zr,Hf)

New Ternary Silver (II) Fluorides: Ag M F₁₄ (M^IV = Zr, Hf) Single crystals of deeply blue violet coloured fluorides Ag₃^IIM₂^IVF₁₄ (M^IV = Zr, Hf) have been obtained by heating powder samples under F₂/N₂ (1:2) at T ≈? 600°C. The isotypic compounds crystallizes monoclinic with a = 924.9, b = 668.6, c = 907.3 pm, β = 90.30° (Ag₃Hf₂F₁₄) and a = 922.5, b = 667.6, c = 906.3 pm, β = 91.30° (Ag₃Zr₂F₁₄) (Four circle diffractometer data, Philips PW 1100), spcgr. C2/m-C_2h³ (No. 12), Z = 2. There are two different sorts of Ag²⁺:Ag(1) with coordination number C.N. [Ag(1)] = 4 + 2 and Ag(2) with C.N.[Ag(2)] = 4 + 4 against F^?. Ag(1) can be substituted by Cu²⁺, Ni²⁺, Zn²⁺, Mg²⁺ (all of blue/red violet colour), Ag(2) by Ca²⁺, Cd²⁺, Hg²⁺ (bright green). From (preliminary) powder data CuAg₂Zr₂F₁₄ with a = 912.3(4), b = 661.2(2), c = 899.4(2) pm, β = 90.70° (3) is isotypic, the other compounds seems to be of closely related type of structure.     

Zur Kenntnis eines Oxoargentato(I)-aurats(III): Ba4AgAuO6

On the Oxoargentato(I)-aurat(III): Ba₄AgAuO₆ The hitherto unknown compound Ba₄AgAuO₆ was prepared by oxidizing Ba/Au/Ag alloy with BaO₂/Ba(OH)₂ mixture in closed Ag tubes. X-ray single crystal investigation led to orthorhombic symmetry space group D-Cmcm; a = 13.275; b = 5.782; c = 11.396 Å; Z = 4. Ba₄AgAuO₆ shows distorted pentagonal bipyramidal polyhedra around Ba²⁺ and square planar AuO₄ polygones. Ag⁺ shows an unusual 2 + 2 coordination by O^2?.     

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.     

Zur Struktur der basischen Diquecksilber(I)-nitrate. III. Kristallstruktur des Hg4O2(NO3)2

Crystal Structure of the Basic Dimercury(I) Nitrates. III. Crystal Structure of Hg₄O₂(NO₃)₂ Hg₄O₂(NO₃)₂ crystallizes monoclinic, space group P2₁/a – standard setting P2₁/c (C) – with a = 1158.0(2), b = 666.4(1), c = 553.3(1) pm, β = 98.82(1)° and Z = 2. The structure determination from single crystal diffractometer data (AgKα, 1170 I₀(hkl), numerical absorption corrections applied) resulted in a final R = 0.0512 (R_w = 0.0685). The mixed valence compound is built up of puckered layers [(Hg^II)_2/2O(Hg)_1/2]⁺ parallel (201). Within the layers there are exclusively covalent Hg? Hg and Hg? O bonds; whereas the linkage between the layers is achieved by weak Hg^I? O contacts and by nitrate ions functioning as weak bridging ligands for mercury atoms. This layer structure explains the distinct cleavage of crystals of Hg₄O₂(NO₃)₂.     

Zwei neue Verbindungen mit Zink in tetragonal pyramidaler Koordination: BaZnDy2O5 und Ba1,25ZnHo2O5,25 (Ba5Zn4Ho8O21)

New Compounds with Zinc in Square Pyramidal Coordination: BaZnDy₂O₅ and Ba_1.25ZnHo₂O_5.25 (Ba₅Zn₄Ho₈O₂₁). Single crystals of (I): BaZnDy₂O₅ and (II): Ba₅Zn₄Ho₈O₂₁ were prepared by high temperature reactions and investigated by X-ray technique. (I) belongs to the BaCuLn₂O₅ type, space group D-Pbnm; a = 7.084; b = 12.368; c = 5.728 Å, Z = 4. (II) is isotypic to Ba₅Mn₄Ln₈O₂₁, space group C-I4/m; a = 13.779; c = 5.707 Å, Z = 2. The two different structure types are caused by the small difference in the composition of 0.25 BaO. Analogies and differences will be discussed. In addition the lattice constants of powder samples of Ba₅Zn₄Ln₈O₂₁ (Ln = Eu, Gd, Dy, Ho, Er and Y) are given.     

Ba2BiV3O11 mit Bismut in geschlossener Koordination

Ba₂BiV₃O₁₁ containing Bismuth within closed Coordination A new barium bismuth oxovanadate, Ba₂BiV₃O₁₁, was prepared and investigated by X-Ray single crystal technique. It crystallizes with monoclinic symmetry space group C—P2₁/a, lattice constants a = 24.6473; b = 7.7347; c = 5.6375 Å, β = 103.16°; Z = 4. Octahedra arround Bi³⁺, tetrahedra and double tetrahedra arround V⁵⁺ form a tunnel structure. The tunnel positions are occupied by Ba(2).     

Über hexagonale Perowskite mit Kationenfehlstellen. XXVI. Ba12Ba2 2/3M 1/3□2O33□3 (MV = Nb,Ta) – die ersten Stapelvarianten eines rhomboedrischen 36 L-Typs

On Hexagonal Perovskites with Cationic Vacancies. XXVI. Ba₁₂Ba_{2 2/3}M _1/3□₂O₃₃□₃ (M^V = Nb, Ta) – the First Stacking Polytypes of a Rhombohedral 36 L-Type In the systems BaO? MO₅(M^V = Nb, Ta) for a Ba:M^V ratio of 2:1 polymorphism is observed. Here the low temperature modifications are described. They crystallize in a rhombohedral 36 L structure with three formula units Ba₁₂Ba_{2 2/3}M _1/3□₂O₃₃□₃ for the trigonal setting (M^V = Nb: a = 5.92₂ Å; c = 93.₂₅ Å; Ta: a = 5,92₂ Å; s = 93.4 Å).     

Eu3+ und Eu2+ in Oxometallaten der Zusammensetzung MBeLn2O5: SrBeEu2O5 und EuBeNd2O5

Eu³⁺ and Eu²⁺ in Oxides of the Composition MBeLn₂O₅: SrBeEu₂O₅ and EuBeNd₂O₅ Single crystals of (I): SrBeEu₂O₅ and (II): EuBeNd₂O₅ were prepared by CO₂-LASER (I) in air and plasma torch (II) technique in H₂ atmosphere. X-ray investigations led to orthorhombic symmetry, space group D-Pnma; (I): a = 9.488, b = 7.156, c = 6.495 Å; (II): a = 9.534, b = 7.225, c = 6.544 Å, Z = 4. Sr²⁺ and Eu³⁺ as well as Eu²⁺ and Nd³⁺ are in statistical distribution within a Kagomé framework. Both compounds are discussed with respect to the monoclinic form of MBeLn₂O₅.     

LaCl(BO2)2 und Er2Cl2[B2O5]: Zwei Chlorid‐Oxoborate dreiwertiger Lanthanide

LaCl(BO₂)₂ and Er₂Cl₂[B₂O₅]: Two Chloride Oxoborates of Trivalent Lanthanides Er₂Cl₂[B₂O₅] is obtained as single crystals by the reaction of ErCl₃, Er₂O₃ and B₂O₃ with an excess of ErCl₃ as flux in evacuated silica tubes after two weeks at 850 °C. The compound crystallizes as long, pale pink needles and appears to be air‐ and water‐resistant. Single‐crystalline LaCl(BO₂)₂ emerges from the reaction of La₂O₃, LaCl₃, and B₂O₃ with an excess of B₂O₃ as flux in evacuated silica tubes after four weeks at 900 °C. LaCl(BO₂)₂ crystallizes as thin, colourless, air‐ and water‐resistant needles which tend to severe twinning due to their fibrous habit. The crystal structure of Er₂Cl₂[B₂O₅] (orthorhombic, Pbam; a = 1489.65(9), b = 1004.80(6), c = 524.86(3) pm; Z = 4) contains two crystallographically different erbium cations. (Er1)³⁺ resides in pentagonal‐bipyramidal coordination of seven anions while (Er2)³⁺ is surrounded by only six anions with the shape of an octahedron. The planar oxodiborate units [B₂O₅]^4— consisting of two vertex‐shared [BO₃]^3— triangles are isolated according to {([BOO]₂)^4—}. LaCl(BO₂)₂ crystallizes isostructurally with PrCl(BO₂)₂ in the triclinic space group P1¯ (a = 423.52(4), b = 662.16(7), c = 819.33(8) pm; α = 82.081(8), β = 89.238(9), γ = 72.109(7)°; Z = 2). The characteristic unit consists of endless chains built up by corner‐linked [BO₃]^3— triangles. These quasi‐planar zigzag chains of the composition {[(B1)OO(B2)OO]^2—} (≡ {[BO₂]^—} run parallel [100]. The La³⁺ cations exhibit coordination numbers of ten and are coordinated by three Cl^— and seven O^2— anions.     

Zur Kristallstruktur von Cu2M(BO3)O2 (M = Fe3+, Ga3+)

The Crystal Structure of Cu₂M(BO₃)O₂ (M = Fe³⁺, Ga³⁺) Single Crystals of the compounds Cu₂M(BO₃)O₂ (M = Fe³⁺ (I), Ga³⁺ (II)) were obtained by a B₂O₃ flux-technique. They crystallize in a monoclinic distorted variant of a Ludwigite structure with a partly ordered metal distribution. X-ray investigations on single crystals led to the space group C–P2₁/c (No. 14); I: a = 3.108(1); b = 12.003(1); c = 9.459(3) Å; b? = 96.66(3)°; Z = 4 and II: a = 3.1146(2); b = 11.921(3); c = 9.477(2) Å; b? = 97.91(2)°; Z = 4. All metal-sites are distorted octahedraly coordinated by oxygen-ions. The structure contains isolated planar BO₃-units and oxygen which is not coordinated to boron.     

Oxygenation of Co(II) Complexes with Tripodal Ligands

The kinetics of O₂-uptake of five-coordinated Co²⁺/tren complexes (tren = 2,2′, 2″-tris(2-aminoethyl)amine) have been studied extensively. The kinetics of formation of (tren)Co(O₂, OH)Co(tren)³⁺ exhibits two steps. The rate law of O₂-addition, the first step, was of the form: rate = (k[H⁺] + kK_a)/([H⁺] + K_a) [Co(tren)²⁺][O₂]. Second-order rate constants k = 220 ± 19 M ^?1s^?1 and k = 1.8 ± .035 · 10³M ^?1s^?1 agreed well from O₂-uptake and (stopped-flow) spectrophotometric measurements. The protonation constant of the hydroxo complex obtained by equlibrium measurements (spectrophotometric and by pH-titration) in anaerobic conditions (pK_a = 10.03) agreed well with that derived from kinetic data (p K_a = 9.93); k and k are about a factor 100 smaller than those for the pseudooctahedral Co(trien) (H₂O). This and the fact that several other Co(II) complexes with five-coordinated geometry do not exhibit oxygen affinity led to the proposal that the oxygenation mechanism for Co²⁺/tren complexes involves fast preequilibria between Co(tren) (H₂O)²⁺ and Co(tren) (H₂O) and only the latter is assumed to be reactive. The enhanced rate at high pH is explained by rate determining H₂O-exchange in the O₂-addition step and the ability of coordinated OH^? to labilize the neighbouring H₂O. This mechanism is furthermore supported by the formation of one kinetically preferred isomer of the peroxo-bridged dicobalt(III) complex (O₂ cis to the tertiary N-atom) and the large negative activation entropy (?30 eu). The second step is the intramolecular bridging reaction: is independent of [Co(tren)²⁺] and [O₂] but exhibits a pH-dependence of the form k₃ = k′₃[H + ]/(K_a + [H⁺]); k_?3 ( = 5 · 10^?5 s^?1) was determined independently and from the two rate constants the equilibrium constant was calculated as ≈ 10⁵. The ligand combination as in Co(tren)²⁺ was shown to provide an excellent balance to form a reversible oxygen carrier; possible reasons for this are discussed.