Na2B2S5 and Li2B2S5: Two Novel Perthioborates with Planar 1,2,4-Trithia-3,5-Diborolane Rings

For the first time perthioborates with trigonal planar coordination of boron were prepared. Na₂B₂S₅ (Pnma, a = 12.545(2) Å, b = 7.441(1) Å, c = 8.271(1) Å, Z = 4) and Li₂B₂S₅ (Cmcm, a = 15.864(1) Å, b = 6.433(1) Å, c = 6.862(1) Å, Z = 4) were obtained by reaction of the metal sulfides with stoichiometric amounts of boron and an excess of sulfur (effective molar ratio M:B:S = 1:1:4) at 600°C (650°C) and subsequent annealing. The non-isotypic structures contain exactly planar [B₂S₅]^2? groups consisting of five-membered B₂S₃ rings with one additional exocyclic sulfur on each of the boron atoms. The alkaline metal cations are four-coordinate (lithium) and (four + four)-coordinate (sodium) respectively.     

Darstellung und Kristallstrukturen von Li4−2xSr2+xB10S19 (x ≈ 0,27) und Na6B10S18. Zwei neue Thioborate mit hochpolymeren Makrotetraeder-Netzwerken

Synthesis and Crystal Structures of Li_4?2xSr_2+xB₁₀S₁₉ (x ≈ 0.27) and Na₆B₁₀S₁₈. Two Novel Thioborates with Highly Polymeric Macro-tetrahedral Networks Li_4?2xSr_2+xB₁₀S₁₉ (x ≈ 0.27) and Na₆B₁₀S₁₈ were prepared from the reaction of strontium sulfide and lithium sulfide (sodium sulfide) with boron and sulfur at 700°C in graphitized silica tubes. Li_4?2xSr_2+xB₁₀S₁₉ (x ≈ 0.27) crystallizes in the monoclinic space group P2₁/c with a = 10.919(2) Å, b = 13.590(3) Å, c = 16.423(4) Å, and β = 90.48(2)°, Na₆B₁₀S₁₈ in the tetragonal space group I4₁/acd with a = 14.415(3) Å, c = 26.137(4) Å. Both structures contain supertetrahedral B₁₀S₂₀ units which are linked through tetrahedral corners to form a three-dimensional polymeric network in the case of Na₆B₁₀S₁₈ and one-dimensional chains in the case of Li_4?2xSr_2+xB₁₀S₁₉ (x ≈ 0.27). All boron atoms are in tetrahedral BS₄ coordination (B? S bond lengths vary from 1.879(5) to 1.951(5) Å (1.875(10) to 1.987(9) Å)). The strontium and lithium (sodium) cations are located within large channels formed by the anions.     

Na2B2Se7, K2B2S7 und K2B2Se7: Drei Perchalkogenoborate mit neuem polymeren Anionengerüst

Na₂B₂Se₇, K₂B₂S₇, and K₂B₂Se₇: Three Perchalcogenoborates with a Novel Polymeric Anion Network Na₂B₂Se₇ (I 2/a; a = 11.863(4) Å, b = 6.703(2) Å, c = 13.811(6) Å, β = 109.41(2)°; Z = 4), K₂B₂S₇ (I 2/a; a = 11.660(2) Å, β = 6.827(1) Å, c = 12.992(3) Å, β = 106.78(3)°; Z = 4), and K₂B₂Se₇ (I 2/a; a = 12.092(4) Å, b = 7.054(2) Å, c = 13.991(5) Å, β = 107.79(3)°; Z = 4) were prepared by reaction of stoichiometric amounts of sodium selenide (potassium sulfide) with boron and sulfur or of potassium selenide and boron diselenide, respectively, at 600°C with subsequent annealing. The crystal structures consist of polymeric anion chains of composition ([B₂S₇]^2?)_n or ([B₂Se₇]^2?)_n formed by spirocyclically connected five-membered B₂S₃ (B₂Se₃) rings and six-membered B₂S₄ (B₂Se₄) rings. The nine-coordinate alkaline metal cations are situated in between.     

Die Perthioborate RbBS3, TIBS3 und TI3B3S10

The Perthioborates RbBS₃, TIBS₃, and Tl₃B₃S₁₀ . RbBS₃ (P2₁/c, a=7.082(2) Å, b=11.863(4) Å, c=5.794(2) Å, β=106.54(2)°) was prepared as colourless, plate-shaped crystals by reaction of stoichiometric amounts of rubidium sulfide, boron, and sulfur at 600°C and subsequent annealing. TlBS₃ (P2₁/c, a=6.874(3) Å, b=11.739(3) Å, c=5.775(2) Å, β=113.08(2)°) which is isotypic with RbBS₃ was synthesized from a sample of the composition Tl₂S · 2 B₂S₃. The glassy product which was obtained after 7 h at 850°C was annealed in a two zone furnace for 400 h at 400→350°C. Yellow crystals of TlBS₃ formed at the warmer side of the furnace. Tl₃B₃S₁₀ (P1 , a=6.828(2) Å, b=7.713(2) Å, c=13.769(5) Å, α=104.32(2)°, β=94.03(3)°, γ=94.69(2)°) was prepared as yellow plates from stoichiometric amounts of thallium sulfide, boron, and sulfur at 850°C and subsequent annealing. All compounds contain tetrahedrally coordinated boron. The crystal structures consist of polymeric anion chains. In the case of RbBS₃ and TlBS₃ nonplanar five-membered B₂S₃ rings are spirocyclically connected via the boron atoms. To obtain the anionic structure of Tl₃B₃S₁₀ every third B₂S₃ ring of the polymeric chains of MBS₃ is to be substituted by a six-membered B(S₂)₂B ring.     

Cs2B2S4 – Ein Salz der dimeren Metathioborsäure

Cs₂B₂S₄ – A Derivative of the Dimeric Metathioboric Acid Cs₂B₂S₄ (structure: I4₁/acd; a = 7.270(1) Å, c = 35.737(7) Å; Z = 8; substructure: I4/mmm; a′ = 5.141(1) Å, c′ = 17.868(4) Å, Z = 2) is prepared by the reaction of cesium sulfide with stoichiometric amounts of boron and sulfur (effective molar ratio M:B:S = 2:2:4) at 600°C and subsequent annealing. The crystal structure contains isolated [B₂S₄]^2? groups consisting of four-membered B₂S₂ rings with two exocyclic sulfur atoms on each of the boron atoms. The cesium cations are nine-coordinate between these rings. The structural feature of two edge-sharing BS₃ groups forming an isolated anion appears for the first time in thioborate chemistry, although it is known as a part of the polymeric network in B₂S₃.     

Li6+2x[B10Se18]Sex (x ≈ 2), ein ionenleitendes Doppelsalz

Li_6+2x[B₁₀Se₁₈]Se_x (x ≈ 2), an Ion‐conducting Double Salt Li_6+2x[B₁₀Se₁₈]Se_x (x ≈ 2) was prepared in a solid state reaction from lithium selenide, amorphous boron and selenium in evacuated carbon coated silica tubes at a temperature of 800 °C. Subsequent cooling from 600 °C to 300 °C gave amber colored crystals with the following lattice parameters: space group I2/a (at 173 K); a = 17.411(1) Å, b = 21.900(1) Å, c = 17.820(1) Å, β = 101.6(1)°. The crystal structure contains a well‐defined polymeric selenoborate network of composition ([B₁₀Se₁₆Se_4/2]^6?)_n consisting of a system of edge‐sharing [B₁₀Se₁₆Se_4/2] adamantanoid macro‐tetrahedra forming large channels in which a strongly disorderd system of partial occupied Li⁺ cations and additional disordered Se^2? anions is observed. The crystal structure of the novel selenoborate is isotypic to Li_6+2x[B₁₀S₁₈]S_x (x ≈ 2) [1]. X‐ray and ⁷Li magic‐angle spinning NMR data suggest that the site occupancies of the three crystallographically distinct lithium ions exhibit a significant temperature dependence. The lithium ion mobility has been characterized by detailed temperature dependent NMR lineshape and spin‐lattice relaxation measurements.     

BaB2S4: Das erste nicht‐oxidische Chalkogenoborat mit trigonal‐planar und tetraedrisch koordiniertem Bor

BaB₂S₄: The first non‐oxidic Chalcogenoborate with Boron in a trigonal‐planar and tetrahedral Coordination Hitherto we know boron in a trigonal‐planar and a tetrahedral coordination within one crystal structure from boron oxides in various compounds. With the novel bariummetathioborate BaB₂S₄ we now report a crystal structure containing BS₃ and BS₄ units in the ratio 1 : 1 forming infinite chains along [001]. BaB₂S₄ was synthesized in a solid state reaction at a temperature of 800 °C from barium sulfide, amorphous boron and sulfur and crystallizes in the monoclinic space group Cc (no. 9) with the following lattice parameters: a = 6.6465(5) Å, b = 15.699(1) Å, c = 6.0306(5) Å, β = 110.96(1)°, Z = 4.     

LiBaBS3 und LiBaB3S6: Zwei neue quaternäre Thioborate mit trigonal-planar koordiniertem Bor

LiBaBS₃ and LiBaB₃S₆: Two New Quaternary Thioborates with Trigonally Coordinated Boron LiBaBS₃ (P2₁/c; a = 7.577(2) Å, b = 8.713(2) Å, c = 8.687(2) Å, β = 116.22(2)°; Z = 4) und LiBaB₃S₆ (Cc; a = 15.116(3) Å, b = 8.824(2) Å, c = 8.179(2) Å, β = 117.46(3)°; Z = 4) were prepared by reaction of stoichiometric amounts of the metal sulfides, boron, and sulfur at 750°C. The anionic part of the structure of the orthothioborate LiBaBS₃ consists of isolated planar [BS₃]^3? anions. The crystal structure of the metathioborate LiBaB₃S₆ contains [B₃S₆]^3? anions formed by six-membered B₃S₃ rings with three exocyclic sulfur atoms. The metal cations are situated between the anion units leading to a ninefold sulfur coordination of the barium atoms and to a fivefold (LiBaBS₃) and fourfold (LiBaB₃S₆) coordination of the lithium atoms.     

Syntheses and Crystal Structures of Rb2B2Se7, Tl2B2Se7, Cs3B3Se10, and Tl3B3Se10: New Perseleno‐selenoborates with Polymeric Anionic Chains

The perseleno‐selenoborates Rb₂B₂Se₇ and Cs₃B₃Se₁₀ were prepared from the metal selenides, amorphous boron and selenium, the thallium perseleno‐selenoborates Tl₂B₂Se₇ and Tl₃B₃Se₁₀ directly from the elements in evacuated carbon coated silica tubes by solid state reactions at temperatures between 920 K and 950 K. All structures were refined from single crystal X‐ray diffraction data. The isotypic perseleno‐selenoborates Rb₂B₂Se₇ and Tl₂B₂Se₇ crystallize in the monoclinic space group I 2/a (No. 15) with lattice parameters a = 12.414(3) Å, b = 7.314(2) Å, c = 14.092(3) Å, β = 107.30(3)°, and Z = 4 for Rb₂B₂Se₇ and a = 11.878(2) Å, b = 7.091(2) Å, c = 13.998(3) Å, β = 108.37(3)° with Z = 4 for Tl₂B₂Se₇. The isotypic perseleno‐selenoborates Cs₃B₃Se₁₀ and Tl₃B₃Se₁₀ crystallize in the triclinic space group P1 (Cs₃B₃Se₁₀: a = 7.583(2) Å, b = 8.464(2) Å, c = 15.276(3) Å, α = 107.03(3)°, β = 89.29(3)°, γ = 101.19(3)°, Z = 2, (non‐conventional setting); Tl₃B₃Se₁₀: a = 7.099(2) Å, b = 8.072(2) Å, c = 14.545(3) Å, α = 105.24(3)°, β = 95.82(3)°, γ = 92.79(3)°, and Z = 2). All crystal structures contain polymeric anionic chains of composition ([B₂Se₇]^2–)_n or ([B₃Se₁₀]^3–)_n formed by spirocyclically fused non‐planar five‐membered B₂Se₃ rings and six‐membered B₂Se₄ rings in a molar ratio of 1 : 1 or 2 : 1, respectively. All boron atoms have tetrahedral coordination with corner‐sharing BSe₄ tetrahedra additionally connected via Se–Se bridges. The cations are situated between three polymeric anionic chains leading to a nine‐fold coordination of the rubidium and thallium cations by selenium in M₂B₂Se₇ (M = Rb, Tl). Coordination numbers of Cs⁺ (Tl⁺) in Cs₃B₃Se₁₀ (Tl₃B₃Se₁₀) are 12(11) and 11(9).     

Synthese und Kristallstrukturen des Zink‐Rhodiumborids Zn5Rh8B4 und der Lithium‐ Magnesium‐Rhodiumboride LixMg5−xRh8B4 (x = 1.1 und 0.5) und Li8Mg4Rh19B12

Synthesis and Crystal Structures of Zinc Rhodium Boride Zn₅Rh₈B₄ and the Lithium Magnesium Rhodium Borides Li_xMg_5?xRh₈B₄ (x = 1.1 and 0.5) and Li₈Mg₄Rh₁₉B₁₂ The title compounds were prepared by reaction of the elemental components in metal ampoules under argon atmosphere (1100 °C, 7 d). In the case of Zn₅Rh₈B₄ (orthorhombic, space group Cmmm, a = 8.467(2) Å, b = 16.787(3) Å, c = 2.846(1) Å, Z = 2) a BN crucible enclosed in a sealed tantalum container was used. The syntheses of Li_xMg_5?xRh₈B₄ (orthorhombic, space group Cmmm, Z = 2, isotypic with Zn₅Rh₈B₄, lattice constants for x = 1.1: a = 8.511(3) Å, b = 16.588(6) Å, c = 2.885(1) Å, and for x = 0.5: a = 8.613(1) Å, b = 16.949(3) Å, c = 2.9139(2) Å) and Li₈Mg₄Rh₁₉B₁₂ (orthorhombic, space group Pbam, a = 26.210(5) Å, b = 13.612(4) Å, c = 2.8530(5) Å, Z = 2) were carried out in tantalum crucibles enclosed in steel containers using lithium as a metal flux. The crystal structures were solved from single crystal X‐ray diffraction data. In both structures Rh atoms reside at z = 0 and all non‐transition metal atoms at z = 1/2. Columns of Rh₆B trigonal prisms running along the c‐axis are laterally connected to form three‐dimensional networks with channels of various cross sections containing Li‐, Mg‐, and Zn‐atoms, respectively. A very short Li‐Li distance of 2.29(7) Å is observed in Li₈Mg₄Rh₁₉B₁₂.     

Sr3(BS3)2 und Sr3(B3S6)2: Zwei neue nicht‐oxidische Chalkogenoborate mit trigonal‐planar koordiniertem Bor

Sr₃(BS₃)₂ and Sr₃(B₃S₆)₂: Two Novel Non‐oxidic Chalcogenoborates with Boron in a Trigonal‐Planar Coordination The thioborates Sr₃(BS₃)₂ and Sr₃(B₃S₆)₂ were prepared from strontium sulfide, amorphous boron and sulfur in solid state reactions at a temperature of 1123 K. In a systematic study on the structural cation influence on this type of ternary compounds, the crystal structures were determined by single crystal X‐ray diffraction. Sr₃(BS₃)₂ crystallizes in the monoclinic spacegroup C2/c (No. 15) with a = 10.187(4) Å, b = 6.610(2) Å, c = 15.411(7) Å, β = 102.24(3)° and Z = 4. The crystal structure of Sr₃(B₃S₆)₂ is trigonal, spacegroup R3¯ (Nr. 148), with a = 8.605(1) Å, c = 21.542(4) Å and Z = 3. Sr₃(BS₃)₂ contains isolated [BS₃]^3— anions with boron in a trigonal‐planar coordination. The strontium cations are found between the layers of orthothioborate anions. Sr₃(B₃S₆)₂ consists of cyclic [B₃S₆]^3— anions and strontium cations, respectively.     

Drei neue Selenoborato-closo-dodekaborate: Synthesen und Kristallstrukturen von Rb8[B12(BSe3)6], Rb4Hg2[B12(BSe3)6] und Cs4Hg2[B12(BSe3)6]

Three Novel Selenoborato- closo -dodecaborates: Syntheses and Crystal Structures of Rb₈[B₁₂(BSe₃)₆], Rb₄Hg₂[B₁₂(BSe₃)₆], and Cs₄Hg₂[B₁₂(BSe₃)₆] The three selenoborates Rb₈[B₁₂(BSe₃)₆] (P1, a = 10.512(5) Å, b = 10.450(3) Å, c = 10.946(4) Å, α = 104.53(3)°, β = 91.16(3)°, γ = 109.11(3)°, Z = 1), Cs₄Hg₂[B₁₂(BSe₃)₆] (P1, a = 9.860(2) Å, b = 10.740(2) Å, c = 11.078(2) Å, α = 99.94(3)°, β = 90.81(3)°, γ = 115.97(3)°, Z = 1), and Rb₄Hg₂[B₁₂(BSe₃)₆] (P1, a = 9.593(2) Å, b = 10.458(2) Å, c = 11.131(2) Å, α = 99.25(3)°, β = 91.16(3)°, γ = 116.30(3)°, Z = 1) were prepared from the metal selenides, amorphous boron and selenium by solid state reactions at 700 °C. These new chalcogenoborates contain B₁₂ icosahedra completely saturated with six trigonal-planar BSe₃ entities functioning as bidentate ligands to form a persubstituted closo-dodecaborate anion. The two isotypic compounds Rb₄Hg₂[B₁₂(BSe₃)₆] and Cs₄Hg₂[B₁₂(BSe₃)₆] are the first selenoborate structures containing a transition metal which are characterized by single crystal diffraction.     

Metalloktaederdoppel in den Clusterverbindungen Gd10I16(C2)2 und Gd10Br15B2/Tb10Br15B2

Gd₁₀I₁₆(C₂)₂ and Gd₁₀Br₁₅B₂/Tb₁₀Br₁₅B₂ Cluster Compounds with M₁₀ Twin Octahedra The compound Gd₁₀I₁₆(C₂)₂ can be prepared from Gd metal, GdI₃ and C at 950 °C. It crystallizes in P1 with a = 10.463(4) Å, b = 16.945(6) Å, c = 11.220(4) Å, α = 99.15(3)°, β = 92.68(3)° und γ = 88.06(3)°. Gd₁₀Br₁₅B₂ is formed between 900 und 950 °C, Tb₁₀Br₁₅B₂ between 900 und 930 °C from stoichiometric amounts of the rare earth metals, tribromide and boron. Both compounds crystallize in the space group P1 for Gd₁₀Br₁₅B₂ with a = 8.984(2) Å, b = 9.816(2) Å, c = 10.552(5) Å, α = 91.14(3)°, β = 114.61(3)° and γ = 110.94(3)° and for Tb₁₀Br₁₅B₂ with a = 8.939(4) Å, b = 9.788(3) Å, c = 10.502(2) Å, α = 91.19(3)°, β = 114.51(3)° and γ = 111.10(2)°. In the crystal structures of all three compounds the rare earth metals form edge‐shared Ln₁₀ twin octahedra. In Gd₁₀I₁₆(C₂)₂ the Gd octahedra are centered with C₂ groups (d_C–C = 1.43(7) Å). In Ln₁₀Br₁₅B₂ (Ln = Gd, Tb) the octahedra contain single boron atoms. The clusters are connected through halide atoms to chains [Ln₁₀(Z)₂X X X ]. Adjacent chains are fused threedimensionally via I I for the Gd iodide carbide and via Br Br for the bromide borides of Gd und Tb. It is interesting to see an identical pattern of connection between the chains for the reduced oxomolybdates, e. g. PbMo₅O₈.     

Syntheses and Crystal Structures of a New Niobium Polysulfide K6Nb4S22 and two New Dimorphic Tantalum Polysulfides K6Ta4S22

The new compounds K₆Nb₄S₂₂ and K₆Ta₄S₂₂ ( I ) have been synthesised by the reaction of NbS₂ or Ta metal in a K₂S₃ flux. Using TaS₂ as educt a second modification of K₆Ta₄S₂₂ ( II ) is obtained. K₆Nb₄S₂₂ and K₆Ta₄S₂₂ (form I ) crystallise in the monoclinic space group C2/c with a = 35.634 (2)Å, b = 7.8448 (4)Å, c = 12.1505 (5)Å, β = 100.853 (5)°, V = 3335.8 (3)ų, and Z = 4 for K₆Nb₄S₂₂ and a = 35.563 (7) Å, b = 7.836 (2)Å, c = 12.139 (2)Å, β = 100.56 (3)°, V = 3325.5 (2)ų, and Z = 4 for K₆Ta₄S₂₂ ( I ). The second modification K₆Ta₄S₂₂ (form II ) crystallises in the monoclinic space group P2₁/c with a = 7.5835 (6)Å, b = 8.7115 (5)Å, c = 24.421 (2)Å, β = 98.733 (9)°, V = 1594.6 (2)ų, and Z = 2. The structures consist of [M₄S₂₂]^6— anions composed of two M₂S₁₁ sub‐units which are linked into M₄S₂₂ units via terminal sulfur ligands. The anions are well separated by the K⁺ cations. Differences between the structures of the title compounds and those with the heavier alkali cations Rb⁺ and Cs⁺ are caused by the different arrangement of the [M₄S₂₂]^6— anions around the cations and the different S^2—/S₂^2— binding modes. The thermal behaviour of both modifications was investigated using differential scanning calorimetry (DSC). From these investigations there is no hint for a polymorphic transition between the two forms. After heating crystals of form II above the melting point and cooling the melt to room temperature a crystalline powder of form I can be isolated.     

Synthesis,Structure and Thermodynamic Property of a New Lithium Borate: Li4[B8O13(OH)2]·3H2O

A new hydrated lithium borate, Li₄[B₈O₁₃(OH)₂]·3H₂O, has been hydrothermally synthesized and characterized by single crystal X‐ray diffraction, FT‐IR spectroscopy, simultaneous TGA‐DTA and chemical analysis. It crystallizes in the triclinic, space group , a=8.4578(5) Å, b=8.7877(5) Å, c=10.8058(7) Å, α=87.740(3)°, β=71.819(3)°, γ=61.569(3)°, Z=2, V=665.26(7) ų, D_c=2.043 g/cm³. Its crystal structure features polyborate anionic layers with the larger odd 13‐membered boron rings constructed by [B₈O₁₃(OH)₂]^4? FBBs. Through designing the thermochemical cycle, the standard molar enthalpy of formation of this borate was determined to be ?(7953.8±6.6) kJ·mol^?1 by using a heat conduction microcalorimeter.     

Neue Alkalimetallchromchalkogenide und ihre Struktursystematik

New Alkali Metal Chromium Chalcogenides and their Structural Classification The compounds RbCr₃S₅, K₃Cr₁₁S₁₈, RbCr₅Se₈ and CsCr₅Se₈ could be obtained in the form of wellshaped crystals via fusion reactions of the alkali metal carbonates with chromium and the corresponding chalcogen. The compounds crystallize in the monoclinic space groups C2/m (RbCr₃S₅: a = 19.372(3) Å, b = 3.498(1) Å, c = 12.119(2) Å, β = 122.78(1)°, Z = 4; K₃Cr₁₁S₁₈: a = 41.876(3) Å, b = 3.463(1) Å, c = 16.315(3) Å, β = 150.07(1)°, Z = 2; RbCr₅Se₈: a = 18.737(2) Å, b = 3.623(1) Å; c = 9.016(1) Å, β = 104.65(1)°, Z = 2; CsCr₅Se₈: a = 18.795(2) Å, b = 3.637(1) Å, c = 9.104(1) Å, β = 104.52(1)°, Z = 2). We propose a structure classification from group-subgroup-relations. MAPLE calculations reveal that the reactions of the binary chalcogenides to yield the ternary compounds are exothermic in each case and are dependent on the chromium/alkali metal ratio in the ternary chalcogenides.     

Li17Sb13S28: A New Lithium Ion Conductor and addition to the Phase Diagram Li2S–Sb2S3

Li₁₇Sb₁₃S₂₈ was synthesized by solid‐state reaction of stoichiometric amounts of anhydrous Li₂S and Sb₂S₃. The crystal structure of Li₁₇Sb₁₃S₂₈ was determined from dark‐red single crystals at room temperature. The title compound crystallizes in the monoclinic space group C2/m (no. 12) with a=12.765(2) Å, b=11.6195(8) Å, c=9.2564(9) Å, β=119.665(6)°, V=1193.0(2) ų, and Z=4 (data at 20 °C, lattice constants from powder diffraction). The crystal structure contains one cation site with a mixed occupation by Li and Sb, and one with an antimony split position. Antimony and sulfur form slightly distorted tetragonal bipyramidal [SbS₅E] units (E=free electron pair). Six of these units are arranged around a vacancy in the anion substructure. The lone electron pairs E of the antimony(III) cations are arranged around these vacancies. Thus, a variant of the rock salt structure type with ordered vacancies in the anionic substructure results. Impedance spectroscopic measurements of Li₁₇Sb₁₃S₂₈ show a specific conductivity of 2.9×10^?9 Ω^?1 cm^?1 at 323 K and of 7.9×10^?6 Ω^?1 cm^?1 at 563 K, the corresponding activation energy is E_A=0.4 eV below 403 K and E_A=0.6 eV above. Raman spectra are dominated by the Sb?S stretching modes of the [SbS₅] units at 315 and 341 cm^?1 at room temperature. Differential thermal analysis (DTA) measurements of Li₁₇Sb₁₃S₂₈ indicate peritectic melting at 854 K.     

Na6[B18Se17]: The First Selenoborato‐closo‐dodecaborate with a Polymeric Chain Anion

Systematic studies on selenoborates containing a B₁₂ cluster entity and alkali metal cations led to the new crystalline phase Na₆[B₁₈Se₁₇] which consists of a icosahedral B₁₂ cluster completely saturated with trigonal‐planar BSe₃ units and sodium counter‐ions. Neighbouring cluster entities are connected in one direction via exocyclic selenium atoms forming the infinite chain anion ([B₁₈Se₁₆Se_2/2]^6–)_∞. The new chalcogenoborate was prepared in a solid state reaction from sodium selenide, amorphous boron and selenium in evacuated carbon coated silica tubes at a temperature of 850 °C. Na₆[B₁₈Se₁₇] crystallizes in the monoclinic space group C2/c (no. 15) with a = 18.005(4) Å, b = 16.549(3) Å, c = 11.245(2) Å, β = 91.35(3)° and Z = 4.     

Y16I19C8B4 – ein Yttriumboridcarbidhalogenid mit B2C4-Einheiten

Y₁₆I₁₉C₈B₄ – a Yttrium Boride Carbide Halide Containing B₂C₄ Units The new compound Y₁₆I₁₉C₈B₄ was prepared from Y, YI₃, C and B at 1050–1150 °C. The structure of a twinned crystal was determined by means of X-ray diffraction (space group P 1¯, a = 12.311(2) Å, b = 13.996(3) Å, c = 19.695(3) Å, α = 74.96(2)°, β = 89.51(2)°, γ = 67.03(2)°, Z = 2). Y₁₆I₁₉C₈B₄ is a semiconductor and contains nearly planar B₂C₄ units which are located in cages built up by 12 yttrium atoms. Assuming (B₂C₄)^12–, these units can be regarded as isoelectronic with B₂F₄. The yttrium cages are connected via faces to form rods, which are surrounded by iodine atoms. Bridging iodine atoms connect the rods so that layers are formed. The characteristic twinning observed can be understood from the geometry of the crystal structure.     

1,2‐Dithioquadratato‐ und 1,2‐Dithiooxalatoindate(III)

Indium(III) chloride forms in water with potassium 1,2‐dithiooxalate (dto) and potassium 1,2‐dithiosquarate (dtsq) stable coordination compounds. Due to the higher bridging ability of the 1,2‐dithiooxalate ligand in all cases only thiooxalate bridged binuclear complexes were found. From 1,2‐dithioquadratate with an identical donor atom set mononuclear trischelates could be isolated. Five crystalline complexes, (BzlMe₃N)₄[(dto)₂In(dto)In(dto)₂] ( 1 ), (BzlPh₃P)₄[(dto)₂In(dto)In(dto)₂] ( 2 ), (BzlMe₃N)₃[In(dtsq)₃] ( 3 ), (Bu₄N)₃[In(dtsq)₃] ( 4 ) and (Ph₄P)[In(dtsq)₂(DMF)₂] ( 5 ), have been isolated and characterized by X‐ray analyses. Due to the type of the complex and the cations involved these compounds crystallize in different space groups with the following parameters: 1 , monoclinic in P2₁/c with a = 14.4035(5) Å, b = 10.8141(5) Å, c = 23.3698(9) Å, β = 124.664(2)°, and Z = 2; 2 , triclinic in P with a = 11.3872(7) Å, b = 13.6669(9) Å, c = 17.4296(10) Å, α = 88.883(5)°, β = 96.763(1)°, γ = 74.587(5)°, and Z = 1; 3 , hexagonal in R3 with a = 20.6501(16) Å, b = 20.6501(16) Å, c = 19.0706(13) Å and Z = 6; 4 , monoclinic in P2₁/c with a = 22.7650(15) Å, b = 20.4656(10) Å, c = 14.4770(9) Å, β = 101.095(5)°, and Z = 4; 5 , triclinic in P with a = 9.2227(6) Å, b = 15.3876(9) Å, c = 15.5298(9) Å, α = 110.526(1)°, β = 100.138(1)°, γ = 101.003(1)°, and Z = 2.