Ga8Ir4B – ein Gallium-Iridiumborid mit isolierten,annähernd quadratisch planaren Ir4B-Gruppen in einer vom CaF2-Typ abgeleiteten Struktur

Ga₈Ir₄B – a Gallium Iridium Boride with isolated, nearly square planar Ir₄B Groups in a Structure derived from the CaF₂ Type The new compound Ga₈Ir₄B (tetragonal, I4₁/acd, a = 853.69(2) pm, c = 2 105.69(6) pm, Z = 8, 614 reflections, 31 parameters, R = 0.034) was prepared by reaction of the elements at 1 100°C. The structure is derived from the CaF₂ type. It contains isolated Ir₄B groups with boron in an unusual, nearly square planar coordination.     

ChemInform Abstract: Y16I19C8B4 — An Yttrium Boride Carbide Halide Containing B2C4 Units.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

Titantetrafluorid – Eine überraschend einfache Kolumnarstruktur

Titanium Tetrafluoride – a Surprising Simple Column Structure For the first time single crystals of TiF₄ have been obtained by solvothermal decomposition of (O₂)₂Ti₇F₃₀ in anhydrous HF. The colourless, transparent needles crystallize orthorhombic in spacegroup Pnma–D (No. 62) with a = 2 281.1, b = 384.8, c = 956.8 pm, Z = 12. The new type of structure is dominated by isolated columns of corner-linked TiF₆-octahedra.     

Das Kupfer–Iridiumborid Cu2Ir4B3 mit einer vom ZnIr4B3‐Typ abgeleiteten Schichtstruktur

The Copper Iridium Boride Cu₂Ir₄B₃ with a Layer Structure Derived from the ZnIr₄B₃ Type The new compound Cu₂Ir₄B₃ (orthorhombic, Cmcm, a = 283.21(2) pm, b = 2540.6(1) pm, c = 281.06(2) pm, Z = 2, 209 reflexions, 18 parameters, R = 0.043) was prepared by reaction of the elements. The structure is related to the ZnIr₄B₃ type. It contains slabs composed of Ir₆B‐ und Ir₆‐prisms which alternate with copper double layers.     

LiBC — ein vollständig interkalierter Heterographit

LiBC — A Completely Intercalated Heterographite LiBC is a new compound composed only from light main group elements. LiBC is synthesized from the elements in sealed niobium ampoules at 770 K, and short annealing at 1 770 K, forming hexagonal platelets with golden lustre. According to Li⁺(BC)^?, boron and carbon form planar hetero graphite layers of the isoelectronic hexagonal boron nitride type. The inter-layer regions are completely filled by lithium (P6₃/mmc; a = 275.2 pm; c = 705.8 pm; hP6; ZrBeSi type). The deformation density of the valence electrons prove the π character of the B? C bonds, as well as a polarization according to (BC^?). Chemical and physical properties indicate a certain range of homogeneity x(Li) ≤ 1. The thermal decomposition and chemical reactions lead to BC products not yet characterized. The oxidation of LiBC obviously runs by a mechanism similar to that of graphite.     

Ti9Se2 – Eine Verbindung mit kolumnaren [Ti9]-Baueinheiten

The Metal-Rich Titanium Selenide Ti₉Se₂ The new compound Ti₉Se₂ has been prepared as hitherto most metal-rich phase in the system titanium-selenium. It crystallizes in the orthorhombic space group Pbam (No. 55) with a = 691.7(2), b = 1 550.5(9), c = 345.4(2) pm. The structure consists of [Ti₉]-strings which are described within the concept of condensed clusters. The Se atoms are coordinated by tricapped trigonal prisms of Ti atoms.     

[BuN(CH2CH2)3NBu]3[Pb5I16] · 4 DMF – ein Iodoplumbat mit nahezu D5h‐symmetrischem Anion

[BuN(CH₂CH₂)₃NBu]₃[Pb₅I₁₆] · 4 DMF – an Iodoplumbate Anion with approximately D _5h Symmetry The star‐shaped anion of [BuN(CH₂CH₂)₃NBu]₃‐[Pb₅I₁₆] · 4 DMF ( 1 ) consists of a cyclic arrangement of five PbI₆ octahedra sharing one common I atom in the centre of an almost planar Pb₅ ring. Compound 1 crystallizes in space group P2₁ with a = 1657.2(1), b = 2029.2(1), c = 1773.6(1) pm, β = 113.238(8)°, Z = 2.     

PdSCl,ein molekulares Palladium(II)-disulfidchlorid mit achtkernigen Pd8(S2)4Cl8−Komplexen und vierfach überbrückenden Disulfidgruppen

PdSCl, a Molecular Palladium(II) Disulfidechloride with Octanuclear Pd₈(S₂)₄Cl₈ Groups and with Tetra Metal-coordinated bridging Disulfide Groups Black crystals of PdSCl have been obtained by reaction of Pd with S₂Cl₂ in closed quartz ampoules at 200°C. The compound is to be formulated as a Palladium(II)-disulfidechloride consisting of Pd₈(S₂)₄Cl₈ molecules with approximately D_4h symmetry. In the octanuclear complexes Pd atoms form a cube, where bridging disulfide groups are found in front of 4 faces and μ₂?bridging Cl atoms on 8 edges. In the monoclinic crystal structure (a = 8.763(2) Å; b = 9.082(2) Å; c = 13.662(4) Å; β = 91.748(23)°; V = 1086.8 ų; Z = 16 PdSCl; Space gr. P2₁/n) the molecules form a cubic closed arrangement.     

Cs4[IrO4], ein neues Iridat mit planarem Anion [IrO4]4−

Cs₄[IrO₄], a New Iridate with Planar Anion [IrO₄]^4? For the first time we obtained black single crystals of Cs₄[IrO₄] by heating intimate mixtures of CsO_0.52 and IrO₂ (molar ratio Cs : Ir = 4.30 : 1.00; “Ag-bomb”, 740°C/86 d). Cs₄[IrO₄] crystallizes monocline, C 2/m, with a = 1031.66(8) pm, b = 671.61(4) pm, c = 660.44(6) pm, b? = 108.118(7)° and Z = 2 in the K₄[IrO₄]-type. The structure has been determined by four-circle-diffractometer data (PW 1100 from Phillips, Ag? Kα , graphite) with 841 I₀(hkl) with I ≥ 3s?(F) (from 947 I₀(hkl) out of 3529 measured reflexes). The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.     

Das erste „Litho-Manganat(V)”︁ mit Schichtstruktur: Cs2{Li[MnO4]}

The First “Litho-Manganate(V)” with Layer-Structure: Cs₂{Li[MnO₄]} By heating intimate mixtures of the oxides [CsO_1,2, Li₂MnO₃; Cs: Mn = 2,3 : 1; Ag-Zylinder, 580°C, 62 d] blue-green single crystals of Cs₂{Li[VO₄]} were obtained for the first time. The new “Litho-Manganate(V)” crystallices orthorhombic (SG: Cmc2₁) with a = 596.08(7), b = 1202.6(1), c = 816.8(1) pm (Guinier-Simon data), Z = 4. It is isotypic with Cs₂{Li[VO₄]} [1]. The structure was determined by four-circle-diffractometer data [Mo? Kα , for 496I_o(hkl) R = 3.1%, R, = 2.4%], parameters see text. The Madelung Part of Lattice Energie, MAPLE and Effective Coordination Numbers, ECoN, these calculated via Mean Fictive Ionic Radii, MEFIR, are calculated and disscussed.     

Opening a New Series of Calcium Boridecarbides with Heterographene Nets by Ca1–x(B,C)6 and Ca1–x(B,C)8 – Two Members of the (CaB2)Cn Compound Series

Ca_1–xB₂C₄ (x ~ 0.08) and Ca_1–xB₂C₆ (x ~ 0.04) are two compounds containing heterographene‐B,C nets which were prepared by solid state synthesis and structurally characterized by X‐ray powder diffraction data. Both compounds crystallize in the space group P6/ mmm (No. 191). The lattice constants are a = 4.55971(5) Å and c = 4.4020(1) Å for CaB₂C₄ and a = 2.58390(5) Å, c = 4.43597(8) Å for CaB₂C₆. The calcium atoms are intercalated between the heterographene (B,C) nets. The calcium atom distribution in Ca_1–xB₂C₆ is disordered, leading to diffuse scattering. A model for this disorder was developed that matches well the observed diffuse scattering observed in the electron diffraction pattern. For Ca_1–xB₂C₆ and its decomposition products magnetic and electric properties are being reported.     

Polytypie und Phasenbreite der Yttriumcarbidbromide 1T- und 3R—Y2Br2C1–x

The Polytypism and Phase Width of the Yttrium Carbide Bromides 1T? Y₂Br₂C_1–x and 3R? Y₂Br₂C_1–x Y₂Br₂C crystallizes in two modifications, 1T? Y₂Br₂C and 3 R? Y₂Br₂C. These are temperature polytypes, and 1 T? Y₂Br₂C is the high temperature form. The transition temperature is 1 400 K. Both modifications show a range of homogeneity with Y₂Br₂C_1–x (0.0 ≤ x ≤ 0.3). For decreasing carbon content the c-lattice parameter increases, the colour of the compound changes from brown-black to bright-silver and the electrical conductivity changes from semiconducting to metallic behaviour. Extended Hueckel calculations indicate metallic conductivity for x > 0 to arise from the occupation of Y? Y metal bonding states above the gap.     

Na10Zn4O9 – ein neues Oxozinkat mit trigonal-planar koordiniertem Zink

Na₁₀Zn₄O₉, a Novel Oxozincate with Trigonal Planar Coordinated Zinc Using a new preparation method for sodium oxometallates we have succeeded in the synthesis of the new ternary oxide Na₁₀Zn₄O₉. Active ZnO reacted with Na₂O generated in situ from NaN₃ and NaNO₂. The compound consists of ZnO₄ tetrahedra which are connected via edges and corners to form layers of the composition ZnO₂. Furthermore, the structure was found to contain isolated, trigonal planar ZnO₃ units. 21 of 60 Na⁺ ions within the unit cell are disordered. Na₁₀Zn₄O₉ crystallizes in the space group R3 m (Nr. 166). The lattice constants are: a = 10.815(3), c = 17.930(7) Å; Z = 6; 8056 reflections; R = 0.062. The sodium ion conductivity at 400°C is 6 × 10^?3 Ω^?1 cm^?1.     

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.     

Ca3Cl2CBN,eine Verbindung mit dem neuen Anion CBN4−

Ca₃Cl₂CBN, a Compound with the New CBN^4? Unit The new compound Ca₃Cl₂CBN was obtained from the reaction of Ca and CaCl₂ with CaCN₂, B and C or with BN and C, in sealed tantalum containers at 900°C. The crystal structure is related with the structure of Ca₃Cl₂C₃ whereas the C₃^4? units (C_2v symmetry) are substituted by isoelectronic CBN^4? anions (C_s symmetry): Ca₃Cl₂CBN, Pnma, a = 1 386.7(9) pm, b = 384.7(3) pm, c = 1 124.7(6) pm, Z = 4; R = 0.055, R_w = 0.036 for 380 independent intensities. The CBN^4? units are located between layers of Ca²⁺ that are interconnected by Cl^?. The bond angle (C? B? N) is 176° and bond distances are d_{C? B} = 144 pm and d_{B? N} = 138 pm, respectively.     

NaAg3S2, ein Thioargentat mit dem Clusteranion [Ag6S4]2−

NaAg₃S₂, a Thioargentate Containing the Anionic Cluster [Ag₆S₄]^2? . Dark-red octahedrally shaped crystals of NaAg₃S₂ could be obtained by the reaction of NaAg(CN)₂ and NaCN in a stream of hydrogen sulfide at 630 K. NaAg₃S₂ crystallizes cubic, a=12.358(1) Å, space group Fd3 m, Z=16. The structure was determined from four-circle diffractometer data. NaAg₃S₂ contains the anionic cluster [Ag₆S₄]^2?. The structure can be traced back to the spinel structure typ. An extended Hückel calculation for the cluster anion, which is considered to be isolated, shows weak bonding silver-silver interactions. NaAg₃S₂ is diamagnetic at room temperature.     

(Bzl4P)2[Bi2I8] – ein Iodobismutat mit fünffach koordiniertem Bi3+‐Ion

(Bzl₄P)₂[Bi₂I₈] – an Iodobismuthate with Penta‐coordinated Bi³⁺ Ions (Bzl₄P)₂[Bi₂I₈] ( 1 , Bzl = –CH₂–C₆H₅) is the first iodobismuthate showing square pyramidal coordination of the Bi³⁺ ion. The anion structure of 1 is compared with that of (Ph₄P)₂[Bi₂I₈(thf)₂] ( 2 ), in which the vacant coordination sites in 1 are occupied by THF ligands. (Bzl₄P)₂[Bi₂I₈] ( 1 ): Space group P1 (No. 2), a = 1300.6(6), b = 1316.8(6), c = 2157.0(9) pm, α = 78.66(3), β = 87.17(3), γ = 60.62(3)°, V = 3151(2)_.10⁶ pm³; (Ph₄P)₂[Bi₂I₈(thf)₂] ( 2 ): Space group P1 (No. 2), a = 1146.5(1), b = 1181.2(1), c = 1249.2(1) pm, α = 92.28(1), β = 105.71(1), γ = 95.67(1)°, V = 1616.6(2)_.10⁶ pm³.     

Sn5Ir6B2 und Sn4Ir7B3: Zinn-Iridiumboride mit eindimensionalen Ir/B-Verbänden

Sn₅Ir₆B₂ and Sn₄Ir₇B₃: Tin Iridiumborides with Onedimensional Ir/B Structural Elements Sn₅Ir₆B₂ (hexagonal, P6 2m, a = 658.97(5) pm, c = 559.19(3) pm, Z = 1, 391 reflexions, 16 parameters, R = 0.037) and Sn₄Ir₇B₃ (hexagonal, P6₃/m, a = 926.63(5) pm, c = 563.19(3) pm, Z = 2, 323 reflexions, 24 parameters, R = 0.045) were prepared by reaction of the elements. Their structures were determined by means of single crystal X-ray methods. The structure of Sn₅Ir₆B₂ may be derived from the Fe₂P type and contains columns of boron centered trigonal Ir prisms sharing their triangular faces. In the structure of Sn₄Ir₇B₃ six of these columns are connected to form a large column with hexagonal cross section. Only every second prism therein is occupied by a boron atom. In both structures these onedimensional Ir/B structural elements are embedded in a matrix of tin atoms composed of Sn-centered Sn₆ prisms twice as long as the Ir₆ prisms.     

Zur elektronischen Struktur von [Y9C4O]I8

On the Electronic Structure of [Y₉C₄O]I₈ The new [Y₉C₄O]I₈ structure exhibits striking similarities with layered structures of the well-known rare-earth metal carbide halides [M₂C]X₂ and [M₂C₂]X₂ (M = rare-earth metal, X = halide) which already have been studied concerning their electronic structures and conductivities. In contrast to the last compounds, [Y₉C₄O]I₈ formally contains one extra electron. This electron appears to be delocalized in various metallic orbitals. The oxygen atoms which are located in the bent sections in the metal double layers as well as the halide double layers in the structure are considered to act as barriers for electronic mobility. Therefore a one-dimensional metallic conductivity is expected to be dominant.     

Tl4Pd3Cl10 – eine Verbindung mit neuartiger [(PdCl2Cl2/2)4]4–‐Baugruppe

Tl₄Pd₃Cl₁₀ – A Compound with a New [(PdCl₂Cl_2/2)₄]^4– Group Single crystals of Tl₄Pd₃Cl₁₀ can be obtained by hydrothermal synthesis. They show tetragonal symmetry with lattice parameters a = 15.956(1) Å and c = 14.146(1) Å, Z = 8 and space group I42d (No. 122). The atomic arrangement of Tl₄Pd₃Cl₁₀ is explored by X‐ray crystal structure analysis. Tl₄Pd₃Cl₁₀ is the first example of a new structural type with a hitherto not isolated tetramer [(PdCl₂Cl_2/2)₄]^4– group.