Notiz über einen Perowskit der Zusammensetzung BaInO2,5

A Non-stoichiometric Perovskite: BaInO_2.5 Single crystals of BaInO_2.5 were prepared by solid state reactions. Out of X-ray diffraction measurements we found a perovskite structure (a = 4.219(2) Å space group O_h¹–Pm3m, Z = 1). BaInO_2.5 is a rare example of a defect perovskite compound with a pure M³⁺ metal ion and an alkaline earth element.     

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.     

Eine kubische Hochtemperaturform von CaTa2O6

About a Cubic Modification of CaTa₂O₆ Single crystals of cub.-CaTa₂O₆ were prepared with a CO₂-Laser-technique. X-ray investigations lead to a cubic symmetry (space group Pm3? T_h¹, a = 7.78 Å, Z = 4). Ta⁵⁺ and O^2? occupy nearly the positions of this ions in the Perovskite structure. For this reason there is a similarity to Ca_0.5TaO₃. The decisive difference to the Ca_0.5TaO₃ is a ordered distribution of Ca²⁺.     

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 Kristallstruktur von KMgCu4V3O13

Synthesis and Crystal Structure of KMgCu₄V₃O₁₃ . Single crystals of KMgCu₄V₃O₁₃ were prepared by supercooled melts. It crystallizes with monoclinic symmetry space group C–P2₁/m (Nr. 11), unit cell dimensions: a = 10.7144 Å, b = 6.0282 Å, c = 8.3365 Å, β = 98.075°, Z = 2. The crystal structure is closely related to the BaMg₂Cu₈O₆O₂₆ type. Cu²⁺ occurs in an unusual trigonal bipyramidal coordination.     

Neue Oxometallate vom BaCuSm2O6-Typ: BaCoHo2O5, BaCoYb2O5 und vom BaNiLn2O5-Typ: BaCoEr2O5

Inhaltsübersicht. (I) BaCoHo₂O₅, (II) BaCoYb₂O₅ und (III) BaCoEr₂O₅ wurden neu dargestellt und an Einkristallen mit Röntgenbeugungsmethoden die Kristallstruktur bestimmt. (I) und (II) gehören zum BaCuSm₂O₅-Typ mit (I): A = 12,267; b = 5,714; c = 7,064 Å; Z = 4; (II): A = 12,138; b = 5,662; c = 7,004 Å; Z = 4. Beide kristallisieren in der Raumgruppe D¹⁶_2h–Pnma. (III) kristallisiert im BaNiLn₂O₅-Typ, Raumgruppe D²⁵_2h–Immm mit a = 3,734; b = 5,770; c = 11,421 Å; Z = 2. Die Koordination um Co²⁺ wechselt von (I, II) nach (III) von tetragonal pyramidal nach oktaedrisch. New Oxides of the BaCuSm₂O₅-Type: BaCoHo₂O₅, BaCoYb₂O₅, and of the BaNiLn₂O₅ Type: BaCoEr₂O₅ (I) BaCoHo₂O₅, (II) BaCoYb₂O₅, and (III) BaCoEr₂O₅ are new compounds prepared by high temperature reactions. X-ray single crystal work show: (I) and (II) belong to the BaCuSm₂O₅-type (space group D¹⁶_2h-Pnma, Z = 4). (I): A = 12.267; b = 5.714; c = 7.064 Å; (II): A = 12.138; b = 5.662; c = 7,004 Å. (III) crystallizes with BaNiLn₂O₅-structure, space group D²⁵_2h-Immm; Z = 2; a = 3.734; b = 5.770; c = 11.421 Å; within (I) and (II) Co²⁺ has a tetragonal pyramidal coordination by oxygen. The coordination changes in (III) to a compressed octehedral O^2– surrounding.     

Synthese und Kristallstrukturen der Calcium‐Iridiumsilicide Ca3Ir4Si4 und Ca2Ir2Si

Synthesis and Crystal Structures of the Calcium Iridium Silicides Ca₃Ir₄Si₄ and Ca₂Ir₂Si The new compounds Ca₃Ir₄Si₄ und Ca₂Ir₂Si were prepared by reaction of the elemental components in sealed tantalum ampoules at 1200 °C. Their structures were determined from X‐ray single crystal data. Ca₃Ir₄Si₄(cubic, space group I4¯3m, a = 7.4171(2)Å, Z = 2) crystallizes with the Na₃Pt₄Ge₄ type structure. For Ca₂Ir₂Si (monoclinic, space group C2/c, a = 9.6567(5)Å, b = 5.8252(2)Å, c = 7.3019(4)Å, β = 100.212(2)°, Z = 4) a new structure was found. Chains of edge sharing, heavily distorted SiIr₄‐tetrahedra (Ir‐Si: 2.381 and 2.414Å) are connected via short Ir—Ir‐contacts (2.640Å) to form an open Ir/Si‐framework accommodating a three‐dimensional arrangement of calcium atoms (Ca—Ca: 3.413 ‐ 3.948Å).     

Structure and resonance raman spectrum of the linear metal-chain compound bis(1,2-benzoquinonedioximato)-palladium triiodide,Pd(bqd)2I0.5 or Pd(bqd)2(I3)0.17

Struktur und Resonanz-Raman-Spektrum der Linear-Metallketten-Verbindung Bis(1,2-benzochinondioximato)palladiumtriiodid, Pd(bcd)₂I_0,5 bzw. Pd(bcd)₂(I₃)_0,17 Die Gitterstruktur der Titelverbindung wurde durch Beugung von Röntgenstrahlen am Einkristall unter Verwendung von MoKα-Strahlung auf einem Syntex P2₁, computerkontrollierten Diffraktometer ermittelt. Die kristallographischen Daten lauten: (PdC₁₂H₁₀N₄O₄)₂I, Molgew. = 888,19; tetragonale Raumgruppe P4/mcc (D_2h⁴); a = b = 15,977 Å, c = 6,371 Å; Z = 2; V = 1626,3 ų; D_rö = 1,81 g/cm³, D_beob = 1,79 g/cm³. Das Gitter kristallisiert mit ausgedehnten, geradlinigen Ketten von partiell oxidierten Pd-Ionen (dessen durchschnittliche Oxydationszahl rund +2,17 beträgt), d. h. die planaren Pd(bcd)₂-Komplexe sind entlang der c-Achse übereinander gestapelt mit einem regelmäßigen Pd—Pd-Abstand von 3,185 Å (1/2 c). Resonanz-Raman-Spektren der Verbindung (polykristalline Proben) wurden mit Hilfe einer Laser-Anregungsquelle (ν₀ = 5145 Å) bei Raumtemperatur aufgenommen. Die Spektren zeigen ausschließlich die charakteristischen Absorptionsbanden von unsymmetrischen I₃^?-Ionen an. Die Ergebnisse lassen darauf schließen, daß der Beitrag der Iodketten zu elektronischen Festkörperanisotropien in dieser Art von quasi-eindimensionalen Materialien vernachlässigbar klein ist.     

Zur Verbindungsbildung von MeO:M2O3. VI. Darstellung und Strukturaufklärung von Sr1,33 Pb0,67 Al6O11

Compound Formation MeO: M₂O₃. VI. Synthesis and Structure Determination of Sr_1,33 Pb_0,67 Al₆O₁₁ Single crystal of Sr_1,33Pb_0.67Al₆O₁₁ could be prepared with a PbO flux. (Space group D–Pnnm, a = 22.13, b = 4.88, c = 8.42 Å, Z = 4) Sr²⁺ and Pb²⁺ are statistically intercalated into a framework of AlO₆ octahedra and AlO₄ tetrahedra. The typical coordination of Sr²⁺ and Pb²⁺ is realized by occupying different positions in the same cavern.     

Zum System K2O/PbO. Zur Kenntnis von K2Pb2O3

On the System K₂O/PbO: The Crystal Structure of K₂Pb₂O₃ Orange-coloured single crystals of K₂Pb₂O₃ crystallize by means of 4-circle-Diffractometer data (237 of 238 possible hkl, R = 5.9₉%, MoKα) cubic with a = 8.41₉ Å, Z = 4, in space group I2₁3?T⁵, parameter see text. We find a superstructure of the perovskite type of structure, where, concerning the formula KPbO_3/2, half of the O^2? ions are omitted systematically, without loosing the 3-Dimensional arrangement of order. Pb²⁺ is surrounded by 3 K⁺ by 6 O^2? and O^2? by 2 Pb²⁺ and 4 K⁺. The Madelung Part of the Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, are calculated and discussed.     

Tetra- and hexaatomic cyclic clusters of main-group elements (XY)2 and (XY)3: an ab initio and density functional study

The electronic and molecular structure of planar (cyclic and linear) tetra- and hexaatomic clusters (XY) _n (XY = CC, BN, BeO, LiF; n = 2, 3) was studied using the ab initio CCD(full)/6-311+G** method and density functional approach (B3LYP/6-311+G**). The stability of cyclic clusters C₆, B₃N₃, and Be₃O₃ with D_3h symmetry is mainly determined by the aromaticity of their -electron systems.     

Die Kristallstruktur von Lithiummesitolat [{LiOC6H2-2,4,6-(CH3)3}4(THF)3]

X-Ray Structure of [{LiOC₆H₂-2,4,6-(CH₃)₃}₄(THF)₃] The title compound crystallized from a THF/OEt₂ solution. Its crystal structure (monoclinic, P2₁/c, a = 21.362(3), b = 13.441(2), c = 17.188(2) Å, β = 98.39(1)°, Z = 4, R = 0,0911, wR² = 0,2562) is built up by cuban-like tetrameric units. Three of the four Li cations attain a coordination number of four by binding to an additional THF molecule. Li(4) without THF coordination has a short distance to one ortho-methyl group (Li(4)…C(27) 2.669(10) Å). The Li–O_ph bonding distances vary from 1.869(10) to 2.051(10) Å (average 1.97 Å); the average bonding distance for Li–O_THF is 2.012(10) Å. Averaged bonding angles for Li–O_ph–Li′ and O_ph–Li–O′_ph amount to 84.4(4)° and 95.4(4)°, respectively. The Li…Li distances significantly differ from each other. They range from 2.556(12) to 2.739(11) Å (average 2.65(1) Å).     

Einkristall-Röntgenstrukturanalyse von Sr3TiGa10O20

Single Crystal X-Ray Analysis of Sr₃TiGa₁₀O₂₀ Single crystals of Sr₃TiGa₁₀O₂₀ were prepared by recrystallisation of a molten oxide mixture and investigated by X-Ray technique. It crystallizes with monoclinic symmetry, space group C–C2/m, a = 15.451, b = 11.579, c = 5.051 Å, β = 108.57°, Z = 2. Sr₃TiGa₁₀O₂₀ belongs to the Pb₃GeAl₁₀O₂₀ type, showing Ga³⁺ in tetrahedral and octahedral coordination. The octahedral coordinated point positions are occupied by Ga³⁺ and Ti⁴⁺ statistically.     

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.     

Preparation and crystal data for two trimetaphosphate tellurates: Te(OH)6 · 2Na3P3O9 · 6H2O and Te(OH)6 · K3P3O9 · 2H2O

Te(OH)₆ · 2Na₃P₃O₉ · 6H₂O, is hexagonal (P6₃/m) with a = 11,67(1), c = 12,12(1) Å, Z = 2 and D_x = 2,225 g/cm³. Te(OH)₆ · K₃P₃O₉ · 2H₂O, is monoklin (P2₁/c) with a = 19,61(5), b = 7,456(1), c = 14,84(6) Å, = 108,01(4), Z = 4 and D_x = 2,506 g/cm³. Both compounds are the first examples of phosphate tellurates in which the anion phosphate is condensed to the ring anion P₃O₉. As in phosphate tellurates already described the phosphate groups are independent of the TeO₆ octahedra.     

Cs2Ba(O3)4 · 2 NH3, das erste ionische Erdalkaliozonid

Cs₂Ba(O₃)₄ · 2 NH₃, the First Ionic Alkaline Earth Metal Ozonide Cs₂Ba(O₃)₄ · 2 NH₃ is the first ionic ozonide containing an alkaline earth metal cation. Its synthesis has been achieved via partial cation exchange of CsO₃ dissolved in liquid ammonia. According to a single crystal X‐ray structure determination (Pnnm; a = 6.312(2) Å, b = 12.975(3) Å, c = 8.045(2) Å; Z = 2; R₁ = 4.6%; 848 independent reflections) ozonide anions, cesium cations and ammonia molecules form a CsCl‐type arrangement, where Cs⁺ and NH₃ occupy one half of the cation sites, each. Ba²⁺ is coordinated by four ozonide groups and two ammonia molecules. Because of a short hydrogen bond to one of the terminal oxygen atoms, the respective O–O‐distance in the ozonide ion is longer than the other. The shortest intermolecular O–O‐distance ever observed in ionic ozonides has been found in this compound, which can be taken as a first clue for the radical ozonide anion to dimerize like the isoelectronic SO₂^– does.     

Synthesis and Characterization of Three Homoleptic Bismuth Silanolates: [Bi(OSiR3)3] (R = Me,Et, iPr)

The bismuth tris(triorganosilanolates) [Bi(OSiR₃)₃] ( 1 , R = Me; 2 , R = Et; 3 , R = iPr) were prepared by reaction of R₃SiOH with [Bi(OtBu)₃]. Compound 1 crystallizes in the triclinic space group with Z = 2 and the lattice constants a = 10.323(1) Å, b = 13.805(1) Å, c = 21.096(1) Å and α = 91.871(4)°, β = 94.639(3)°, γ = 110.802(3)°. In the solid state compound 1 is a trimer as result of weak intermolecular bismuth‐oxygen interactions with Bi–O distances in the range 2.686(6)–3.227(3) Å. The coordination at the bismuth atoms Bi(1) and Bi(3) is best described as 3 + 2 coordination whereas Bi(2) shows a 3 + 3 coordination. The intramolecular Bi–O distances fall in the range 2.041(3)–2.119(3) Å. Compound 3 crystallizes in the orthorhombic space group Pbcm with Z = 4 and the lattice constants a = 7.201(1) Å, b = 23.367(5) Å and c = 20.893(1) Å, whereas the triethylsilyl‐derivative 2 is liquid. In contrast to [Bi(OSiMe₃)₃] ( 1 ) compound 3 is monomeric in the solid state, but shows similar intramolecular Bi–O distances in the range 1.998(2)–2.065(5) Å. The bismuth silanolates are highly soluble in common organic solvents and strongly moisture sensitive. Compound 1 shows the lowest thermal stability.     

New examples of mixed-ligand bis(hexafluoroacetylacenonato)copper(II) complexes with 3-imidazoline nitroxide radicals at a Cu(C5HF6O2)2∶L=3∶2 ratio (L2=C14H19N2O,L3=C13H17N2O3)

The crystal structures of two (hexafluoroacetylacetonato)copper(II) complexes with 3-imidazoline nitroxide radicals, [Cu(C₅HF₆O₂)₂]₃ (C₁₄H₁₉N₂O)₂ (I) and [Cu(C₅HF₆O₂)₂]₃ (C₁₃H₁₇N₂O₃)₂ (II), have been determined. The compounds are triclinic (PI, Z=1) with a=8.730(2), b=10.357(2), c=21.996(5) Å, α=103.24(2), β=94.03(2), γ=95.04(2)⁰, V=1920(1) ų for I and a=8.679(2), b=14.769(4), c=15.368(4) Å, α=85.58(2), β=96.25(1), γ=104.60(1)⁰, V=1893(1) ų for II. Complexes I and II are molecular. The trinuclear molecules are centrosymmetric relative to the Cu(1) atom. The coordination polyhedron of Cu(1) is a square bipyramid formed by the O atoms of the hfac anions and nitroxide radicals (average Cu?O_hfac 1.92(1) for I and 1.93(1) Å for II; Cu?O_N?O 2.47(1) for I and 2.56(1) Å for II). The coordination polyhedron of Cu(2) is a trigonal bipyramid formed by the O atoms of the hfac anions (Cu?O_hfac 1.91(1)–2.12(1) for I and 1.91(1)–2.09(1) Å for II) and an imine N atom of the radical (Cu(2)?N(2) 2.00(1) for I and 2.03(1) Å for II). The molecules are linked by van der Waals forces.     

Neue Beryllate der Alkalimetalle: Na6Be8O11

Novel Beryllates of the Alkali Metals: Na₆Be₈O₁₁ For the first time transparent, colourless single crystals of Na₆Be₈O₁₁ have been prepared (Na₂O/BeO; Na:Be = 6:8, Ni-tube; 650°, 14 d). The compound crystallizes triclinic (P1 ) with a = 532.1(1) pm, b = 642.4(2) pm, c = 839.1(2) pm, α = 101.7°, γ = 105.8°, Z = 2, d_x = 2.42 g/cm³, d_pyk=2.51 g/cm³. The crystal structure was solved by four-circle diffractometer data [Siemens AED 2, MoKα , R = 7.9%, R_w = 6.2%, 1429 I₀(hkl)]. Effektive Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated.     

Über Oxostannate(II). I. Zur Kenntnis von K2Sn2O3

On Oxostannates(II). I. Information on K₂Sn₂O₃ Hitherto unknown K₂Sn₂O₃ was obtained by heating mixtures of binary Oxides [KO_0.48 + SnO, K:Sn = 1.1:1] under Argon [Al₂O₃ cylinders, 550°C, 24 h or 7 d] as yellow powder or brownish-yellow single crystals, respectively. It crystallizes trigonal-rhombohedral in R3m—D, with a = 6.00₁ Å, c = 14.32₇ Å, Z = 3, d_rö = 4.05 and d_pyk = 3.98 gcm^?3, positions are given in text, R = 2.1₁% for 219 hkl (MoKα, 4-circle diffractometer data).