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.     

Neue Oxogallate der Alkalimetalle: Über K6[Ga2O6] und Rb6[Ga2O6], sowie Na3GaO3 und Cs6[Ga2O6]

New Oxogallates of Alkaline Metals: On K₆[Ga₂O₆] and Rb₆[Ga₂O₆] as well as Na₃GaO₃ and Cs₆[Ga₂O₆] Due to powder and single crystal data K₆[Ga₂O₆] a = 7.09₉; b = 11.11₆; c = 6.48₄ Å; ß = 101.6₆° and Rb₆[Ga₂O₆] a = 7.39₃; b = 11.47₅; c = 6.79₈ Å; ß = 103.5° crystallize isotypic with K₆[Fe₂O₆]; space group C2/m-C₃^2h; As well has been prepared the hitherto unknown Na₃GaO₃ a = 11.48, b = 10.82, c = 6.13 Å, space-group Imcm or I2cm Z = 8; and Cs₆[Ga₂O₆] a = 7.2₆, b = 12.1, c = 7.6₈ Å, ß = 105°, Z = 4, space-group P2₁/a.     

K6[Mn2O6] und K6[Fe2 O6] - ein Vergleich

K₆[Mn₂O₆] and K₆[Fe₂O₆] - a Comparison K₆[Mn₂O₆] has been prepared (dark-red single crystals). The structure (a = 8.88₆, b = 6.76₀, c = 11.39₄ Å, γ = 132.1°, space group P2₁, Z = 2, 1151 symmetry independent reflections hk0–hk9, R = 0.051) shows Al₂Cl₆-like anions [Mn₂O₆]^6?. By unit-cell transformation to the monoclinic setting P2₁/a (a = 6.76₀, b = 11.39₄, c = 6.63₈ Å, β = 96,9°) the structural similarity to K₆[Fe₂O₆] becomes evident. The Madelung Part of Lattice Energy, MAPLE, is calculated.     

Beiträge zum Koordinationsverhalten von Oxidionen in anorganischen Feststoffen. III [1] Mn2P2O7, Mn2P4O12 und Mn2Si(P2O7)2 — Kristallzüchtung,Strukturverfeinerungen und Elektronenspektren von Mangan(II)‐Phosphaten

Contributions on the Bonding Behaviour of Oxygen in Inorganic Solids. III [1] Mn₂P₂O₇, Mn₂P₄O₁₂ und Mn₂Si(P₂O₇)₂ — Crystal Growth, Structure Refinements and Electronic Spectra of Manganese(II) Phosphates By chemical vapour transport reactions in a temperature gradient single crystals of Mn₂P₂O₇ (1050 → 950 °C) and Mn₂P₄O₁₂ (850 → 750 °C) have been obtained using P/I mixtures as transport agent. Mn₂Si(P₂O₇)₂ was crystallized by isothermal heating (850 °C, 8d; NH₄Cl as mineralizer) of Mn₂P₄O₁₂ und SiO₂. In Mn₂Si(P₂O₇)₂ [C 2/c, a = 17.072(1)Å, b = 5.0450(4)Å, c = 12.3880(9)Å, β = 103.55(9)°, 1052 independent reflections, 97 variables, R1 = 0.023, wR2 = 0.061] the Mn²⁺ ions show compressed octahedral coordination (d¯_Mn—O = 2.19Å). The mean distance d¯_Mn—O = 2.18Å was found for the radially distorted octahedra [MnO₆] in Mn₂P₄O₁₂ [C 2/c, Z = 4, a = 12.065(1)Å, b = 8.468(1)Å, c = 10.170(1)Å, β = 119.29(1)°, 2811 independent reflections, 85 variables, R1 = 0.025, wR2 = 0.072]. Powder reflectance spectra of the three pink coloured manganese(II) phosphates have been measured. The spectra show clearly the influence of the low‐symmetry ligand fields around Mn²⁺. Observed d—d electronic transition energies and the results of calculations within the framework of the angular overlap model (AOM) are in good agreement. Bonding parameters for the manganese‐oxygen interaction in [Mn²⁺O₆] chromophors as obtained from the AOM treatment (B, C, Trees correction α, e_σ, e_π) are discussed.     

A Tetranuclear Manganese Cluster with a Star‐Shaped Mn4O6 Core Motif: Directed Synthesis using a Mononuclear Precursor Complex

The tetranuclear manganese(II) complex [Mn₄(ppi)₆](BPh₄)₂ ( 2 ) (Hppi = 2‐pyridylmethyl‐2‐hydroxy phenylimine) is prepared by using the precursor complex [Mn(ppi)₂]·H₂O ( 1 ). Based on UV/Vis‐ and IR‐spectroscopy data in combination with mass spectrometry it has been concluded that 1 is a mononuclear neutral Mn^II complex, in which two ppi ligands chelate the manganese atom. Compound 2 crystallizes in the triclinic space group P1¯ (no. 2), with a = 17.500(3), b = 17.955(4), c = 19.101(4) Å, α = 113.79(3)°, β = 111.33(3)°, γ = 93.91(3)°, V = 4950(2) ų and Z = 2. In the tetranuclear [Mn₄(ppi)₆]²⁺ complex cation Mn(1), Mn(2), and Mn(3) are equivalently coordinated by two deprotonated Hppi ligands leading to a N₄O₂ donor set. The environment of the central Mn(4) is formed by coordination of three [Mn(ppi)₂] fragments resulting in a phenoxo bridged star‐shaped Mn₄O₆ core motif. The average distance of directly adjacent manganese ions is 3.310 Å, whereas the average distance of Mn(1), Mn(2), and Mn(3) among each other is 5.732 Å.     

Über Hexafluorovanadate(III). Cs2MVF6 und Rb2MVF6 (MTl,K und Na); mit einer Bemerkung über Na3VF6

On Hexafluorovanadates(III). Cs₂MVF₆ and Rb₂MVF₆ (M?Tl, K. and Na); with a Remark on Na₃VF₆ By heating the binary fluorides in a closed system we obtained Cs₂TlVF₆ (a = 9.23₄ Å), Cs₂KVF₆ (a = 9.04₇ Å), Rb₂KVF₆ (a = 8.85₅ Å) and Rb₂NaVF₆ (a = 8.46₈ Å), all cubic Elpasolithes of soft green colour as well as Cs₂NaVF₆ (hexagonal a = 6.24 Å, c = 30.58 Å, isotypic with Cs₂NaCrF₆) and Na₃VF₆ (monoclinic a = 5.51₃ Å, b = 5.72₁ Å, c = 7.96₃ Å, β = 90.4₇°, isotypic with Na₃AlF₆). VF₃ (3.0–296.2°K), Cs₂TlVF₆, Cs₂KVF₆ and Rb₂KVF₆ (all from 70–299°K) have been measured magnetically. The spectra of reflection in the range of 9 000 to 33 000 cm^?1 of VF₃ and the new quaternary fluorides are measured and discussed. The Madelung Part of Lattice Energy (MAPLE) is calculated and discussed.     

One‐Dimensional Zinc Selenophosphates: A2ZnP2Se6 (A = K,Rb, Cs)

The new compounds A₂ZnP₂Se₆ (A = K, Rb, Cs) were synthesized via molten salt flux syntheses. The crystals feature one‐dimensional ¹/_∞[ZnP₂Se₆]^2– chains charge balanced by alkali metal ions between the chains. K₂ZnP₂Se₆ crystallizes in the monoclinic space group P2₁/c; cell parameters a = 12.537(3) Å, b = 7.2742(14) Å, c = 14.164(3) Å, β = 109.63(3)°, Z = 4, and V = 1216.7(4) ų. Rb₂ZnP₂Se₆ and Cs₂ZnP₂Se₆ are isotypic, crystallizing in the triclinic space group P$\bar{1}$ . Rb₂ZnP₂Se₆ has cell parameters of a = 7.4944(15) Å, b = 7.6013(15) Å, c = 12.729(3) Å, α = 96.57(3)°, β = 105.52(3)°, γ = 110.54(3)°, Z = 2, and V = 636.6(2) ų. Cs₂ZnP₂Se₆ has cell parameters of a = 7.6543(6) Å, b = 7.7006(6) Å, c = 12.7373(11) Å, α = 97.007(7)°, β = 104.335(7)°, γ = 109.241(6)°, Z = 2, and V = 669.54(10) ų.     

Solvothermal Synthesis and Crystal Structures of Two Thioantimonate(V) Compounds with the [SbS4]3— Anion Acting as a Monodentate Ligand: [Mn(C6H18N4)(C6H19N4)]SbS4 and [Mn(C6H14N2)3]2[Mn(C6H14N2)2(SbS4)2]·6H2O

The two novel thioantimonate(V) compounds [Mn(C₆H₁₈N₄)(C₆H₁₉N₄)]SbS₄ ( I ) and [Mn(C₆H₁₄N₂)₃][Mn(C₆H₁₄N₂)₂(SbS₄)₂]·6H₂O ( II ) were synthesized under solvothermal conditions by reacting elemental Mn, Sb and S in the stoichiometric ratio in 5 ml tris(2‐aminoethyl)amine (tren) at 140 °C or chxn (trans‐1, 2‐diaminocyclohexane, aqueous solution 50 %) at 130 °C. Compound I crystallises in the triclinic space group P1¯, a = 9.578(2), b = 11.541(2), c = 12.297(2)Å, α = 62.55(1), β = 85.75(1), γ = 89.44(1)°, V = 1202.6(4)ų, Z = 2, and II in the monoclinic space group C2/c, a = 32.611(2), b = 13.680(1), c = 19.997(1)Å, β = 117.237(5)°, V = 7931.7(8)ų, Z = 4. In I the Mn²⁺ cation is surrounded by one tetradentate tren molecule, one protonated tren acting as a monodentate ligand and a monodentate [SbS₄]^3— anion yielding a distorted octahedral environment. In II one unique Mn²⁺ ion is in an octahedral environment of three bidentate chxn molecules and the second independent Mn²⁺ ion is coordinated by two chxn ligands and two monodentate [SbS₄]^3— units leading to a distorted octahedral surrounding. The compounds were investigated and characterized with thermal and spectroscopic methods.     

Thio- und Selenomercurate(II). K6[HgS4], K6[HgSe4], Rb6[HgS4] und Rb6[HgSe4]

Thio- and Selenomercurates(II). K₆[HgS₄], K₆[HgSe₄], Rb₆[HgS₄] and Rb₆[HgSe₄] We prepared by annealing intimate mixture of pure samples of K₂S, K₂Se, Rb₂S, and Rb₂Se with HgS or HgSe [360–380°C, 7d, Duran-glass-seal with Argon] with hexagonal Na₆ZnO₄ isotypic new mercurates: K₆[HgS₄] [bright citronic yellow a = 9.98₅, c = 7.65₂ Å], K₆[HgSe₄] [light orange yellow a = 10.3₆, c = 7.88₃ Å], Rb₆[HgS₄] [bright yellow a = 10.3₄, c = 7.94₂ Å], Rb₆[HgSe₄] [orange-red a = 10.7₂, c = 8.19₂ Å]. The crystal structure of K₆ Hgs₄ is elucidated by using diffractometer data of single crystals: P63mc, C⁴_6v, it is R = 6.6% for 304 reflexes [h k o–h k 4, anisotropic refinement MoKα]; for position and parameters see text d_rö = 2.83₅, d_pyk = 2.99 g · cm^?3. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, are calculated and discussed.     

Darstellung und Kristallstruktur von Na2Mn3O7

Synthesis and Crystal-Structure of Na₂Mn₃O₇ Single crystals of Na₂Mn₃O₇ have been grown hydrothermally applying high oxygen pressure (p = 2 kbar). The new compound cystallizes triclinic; space group P1 ; a = 6.636(6) Å, b = 6.854(6) Å, c = 7.548(6) Å, α = 105.76(6)°, β = 106.86(6)°, γ = 111.60(6)°; Z = 2. The crystal structure has been solved and refined to R = 7.9% and R_w = 6.2% (diffractometer data, 1044 independent reflexions). The crystal structure consists of Mn₃O₇^2? anions with manganese coordinated octahedrally by oxygen. These layered anions are hold together by Na⁺ ions (coordination numbers 5 and 6).     

Three Copper(II) Coordination Polymers Constructed by Both Rigid and Flexible Ligands

Three new Copper(II) polymers coordinated by both rigid and flexible ligands, [Cu(bpy)(C₅H₆O₄)]_n ( 1 ), [Cu(bpy)(C₆H₈O₄)]_n ( 2 ), and [Cu₂(bpy)₂(C₆H₈O₄)₂]_n ( 3 ) (bpy = 4,4′‐bipyridine), have been hydrothermally synthesized and structurally characterized. Complex 1 features a box‐like bilayer motif of (4, 4) net. It crystallizes in triclinic space group with cell parameters: a = 8.1395(6) Å, b = 9.43 12(8) Å, c = 10.5473(8) Å, α = 112.1830(1)°, β = 92.423(2)°, γ = 104.752(2)°, V = 716.31(1) ų, Z = 2. Complex 2 crystallizes in triclinic space group with a = 8.8652(4) Å, b = 8.9429(4) Å, c = 10.6390(4) Å, α = 89.520(2)°, β = 69.123(2)°, γ = 75.2440(1)°, V = 758.92(6) ų, Z = 2. Complex 3 crystallizes in monoclinic space group Cc with a = 11.1521(1) Å, b = 15.3961(1) Å, c = 17.7419(1) Å, β = 105.715(3)°, V = 2932.4(5) ų, Z = 4. Complexes 2 and 3 are isomeric with different coordination modes of adipato ligand. Both of them possess the two‐fold interpenetrated 3‐D pcu topological net.     

Neue Oxocuprate (I). Über Cs3Cu5O4, Rb2KCu5O4, RbK2Cu5O4 und K3Cu5O4

New Oxocuprates(I). On Cs₃Cu₅O₄, Rb₂KCu₅O₄, RbK₂Cu₅O₄ and K₃Cu₅O₄ Cs₃Cu₅O₄ light yellow, powder as well as single crystals [a = 10.313(9), b = 7.630(1), c = 14.750(4) Å, β = 106.48(6)°], Rb₂KCu₅O₄ [a = 9.724(2), b = 7.443(0), c = 14.246(2) Å, β = 106.78(8)°], RbK₂Cu₅O₄ [a = 9.561(1), b = 7.411(0), c = 14.111(1) Å, β = 106.76(7)°] and K₃Cu₅O₄ [a = 9.422(1), b = 7.364(1), c = 13.995(2) Å, β = 107.00(2)°] are new prepared. The colour of the powders becomes lighter according to the sequence showed above. K₃Cu₅O₄ shows pale yellow. The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed.     

Extraction and isolation of the One-electron Oxidized [(Zr6Be)Cl18]5− and [(Zr6Be)Cl18]4− Clusters from solid state precursors

One-electron oxidized zirconium chloride clusters were obtained from solid state precursors Rb₅Zr₆Cl₁₈B and K₃Zr₆Cl₁₅Be by dissolution in CH₃CN in the presence of Et₄NCl and isolated as the salts (Et₄N)₄Zr₆Cl₁₈B · 2 CH₃CN and (Et₄N)₅Zr₆Cl₁₈Be · 3 CH₃CN. (Et₄N)₄Zr₆Cl₁₈B · 2 CH₃CN crystallizes in the space group P1 (#2) with a = 12.329(5) Å, b = 12.657(6) Å, c = 13.136(8) Å, α = 118.28(4)°, β = 93.45(4)°, γ = 105.54(3)°, V = 1696(2) ų, and Z = 1. (Et₄N)₅Zr₆Cl₁₈Be · 3 CH₃CN was refined in the space group C2/c (# 15) with a = 24.166(11) Å, b = 13.265(6) Å, c = 25.86(2) Å, β = 104.21(4)°, V = 8037(7) ų, and Z = 4; the space group reflects the pseudo-symmetry of the crystal, the true symmetry of the structure is lower. The removal of one electron from the Zr? Zr bonding HOMO of both clusters results in cluster expansion of similar magnitude in both compounds. Moisture from the added Et₄NCl is the likely oxidant, but the possibility that acetonitrile may be reduced by [(Zr₆Be)Cl₁₈]^6? is not ruled out.     

Alkoholyse von [Fe2(OtBu)6] als einfacher Weg zu neuen Eisen(III)‐Alkoxo‐Verbindungen: Synthesen und Kristallstrukturen von [Fe2(OtAmyl)6], [Fe5OCl(OiPr)12], [Fe5O(OiPr)13], [Fe5O(OiBu)13], [Fe5O(OCH2CF3)13], [Fe5O(OnPr)13] und [Fe9O3(OnPr)21] · iPrOH

Alcoholysis of [Fe₂(O^tBu)₆] as a Simple Route to New Iron(III)‐Alkoxo Compounds: Synthesis and Crystal Structures of [Fe₂(O^tAmyl)₆], [Fe₅OCl(OⁱPr)₁₂], [Fe₅O(OⁱPr)₁₃], [Fe₅O(OⁱBu)₁₃], [Fe₅O(OCH₂CF₃)₁₃], [Fe₅O(OⁿPr)₁₃], and [Fe₉O₃(OⁿPr)₂₁] · ⁿPrOH New alkoxo‐iron compounds can be synthesized easily by alcoholysis of [Fe₂(O^tBu)₆] ( 1 ). Due to different bulkyness of the alcohols used, three different structure types are formed: [Fe₂(OR)₆], [Fe₅O(OR)₁₃] and [Fe₉O₃(OR)₂₁] · ROH. We report synthesis and crystal structures of the compounds [Fe₅OCl(OⁱPr)₁₂] ( 2 ), [Fe₂(O^tAmyl)₆] ( 3 ), [Fe₅O(OⁱPr)₁₃] ( 4 ), [Fe₅O(OⁱBu)₁₃] ( 5 ), [Fe₅O(OCH₂CF₃)₁₃] ( 6 ), [Fe₉O₃(OⁿPr)₂₁] · ⁿPrOH ( 7 ) and [Fe₅O(OⁿPr)₁₃] ( 8 ). Crystallographic Data: 2 , tetragonal, P 4/n, a = 16.070(5) Å, c = 9.831(5) Å, V = 2539(2) ų, Z = 2, d_c = 1.360 gcm^?3, R₁ = 0.0636; 3 , monoclinic, P 2₁/c, a = 10.591(5) Å, b = 10.654(4) Å, c = 16.740(7) Å, β = 104.87(2)°, V = 1826(2) ų, Z = 2, d_c = 1.154 gcm^?3, R₁ = 0.0756; 4 , triclinic, , a = 20.640(3) Å, b = 21.383(3) Å, c = 21.537(3) Å, α = 82.37(1)°, β = 73.15(1)°, γ = 61.75(1)°, V = 8013(2) ų, Z = 6, d_c = 1.322 gcm^?3, R₁ = 0.0412; 5 , tetragonal, P 4cc, a = 13.612(5) Å, c = 36.853(5) Å, V = 6828(4) ų, Z = 4, d_c = 1.079 gcm^?3, R₁ = 0.0609; 6 , triclinic, , a = 12.039(2) Å, b = 12.673(3) Å, c = 19.600(4) Å, α = 93.60(1)°, β = 97.02(1)°, γ = 117.83(1)°, V = 2600(2) ų, Z = 2, d_c = 2.022 gcm^?3, R₁ = 0.0585; 7 , triclinic, , a = 12.989(3) Å, b = 16.750(4) Å, c = 21.644(5) Å, α = 84.69(1)°, β = 86.20(1)°, γ = 77.68(1)°, V = 4576(2) ų, Z = 2, d_c = 1.344 gcm^?3, R₁ = 0.0778; 8 , triclinic, , a = 12.597(5) Å, b = 12.764(5) Å, c = 16.727(7) Å, α = 91.94(1)°, β = 95.61(1)°, γ = 93.24(2)°, V = 2670(2) ų, Z = 2, d_c = 1.323 gcm^?3, R₁ = 0.0594.     

Rubidiumhexaamidolanthanat und -neodymat,Rb3[La(NH2)6] und Rb3[Nd(NH2)6]; Strukturverwandtschaft zu K3[Cr(OH6)] und K4CdCl6

Rubidium Hexaamidolanthanate and -neodymate, Rb₃[La(NH₂)₆] and Rb₃[Nd(NH₂)₆]; Compounds. Structurally Related to K₃[Cr(OH)₆] and K₄CdCl₆ Colourless Rb₃[La(NH₂)₆] (a = 12.298(4) Å, c = 13.759(2) Å, N = 6, R3 c) and pale blue Rb₃[Nd(NH₂)₆] (a = 12.199(6) Å, c = 13.626(4) Å, N = 6, R32) have been prepared by the reaction of the corresponding metals (Rb: La resp. Nd = 3:1) with NH₃(P(NH₃) = 4–4.5 kbar) at 300°C. Single crystal x-ray methods gave their structures. It is shown by space group relations that these compounds are structurally related to one another and to further ternary amides as well as to K₃[Cr(OH)₆] and K₄CdCl₆.     

Synthesis,Structural Characterization,and Cation Transport of Tripotassium Pentabismuth Arsenate K3Bi5(AsO4)6

During the exploration of the K₂O-Bi₂O ₃ -As₂O₅ system, single crystals of a new arsenate of trivalent bismuth, K₃Bi₅(AsO₄) ₆, were isolated by solid state reaction at 600°C. The title compound crystallizes in the monoclinic system, space group C2/c (N°15) with a = 18.257(2) Å, b = 7.260(1) Å, c = 20.130(4) Å, β = 119.86(1)°, and Z = 4. Its structure consists of a three-dimensional framework made up of AsO₄ tetrahedra and BiO₆ and BiO₇ polyhedra sharing edges and corners, delimiting cavities wherein K⁺ ions reside. This compound exhibits a potassium ion conductivity but with rather low conductivity value.     

Synthesis and Characterization of the Rubidium Thiophosphate Rb6(PS5)(P2S10) and the Rubidium Silver Thiophosphates Rb2AgPS4, RbAg5(PS4)2 and Rb3Ag9(PS4)4

The metal thiophosphates Rb₂AgPS₄ ( 2 ), RbAg₅(PS₄)₂ ( 3 ), and Rb₃Ag₉(PS₄)₄ ( 4 ) were synthesized by stoichiometric reactions, whereas Rb₆(PS₅)(P₂S₁₀) ( 1 ) was prepared with excess amount of sulfur. The compounds crystallize as follows: 1 monoclinic, P2₁/c (no. 14), a = 17.0123(7) Å, b = 6.9102(2) Å, c = 23.179(1) Å, β = 94.399(4)°; 2 triclinic, P$\bar{1}$ (no. 2), a = 6.600(1) Å, b = 6.856(1) Å, c = 10.943(3) Å, α = 95.150(2)°, β = 107.338(2)°, γ = 111.383(2)°; 3 orthorhombic, Pbca (no. 61), a = 12.607(1) Å, b = 12.612(1) Å, c = 17.759(2) Å; 4 orthorhombic, Pbcm (no. 57), a = 6.3481(2) Å, b = 12.5782(4) Å, c = 35.975(1) Å. The crystal structures contain discrete units, chains, and 3D polyanionic frameworks composed of PS₄ tetrahedral units arranged and connected in different manner. Compounds 1 – 3 melt congruently, whereas incongruent melting behavior was observed for compound 4 . 1 – 4 are semiconductors with bandgaps between 2.3 and 2.6 eV and thermally stable up to 450 °C in an inert atmosphere.     

Synthesis and Crystal Structure of Rb6Ta4S22: The First Tantalum Polysulfide Composed of the Dimeric Complex Anion [Ta4S22]6–

The reaction of Rb₂S₃, Ta and S in a 1.3 : 1 : 5.6 molar ratio at 400 °C yields red‐orange crystals of the new ternary compound Rb₆Ta₄S₂₂ being the first tantalum polysulfide containing the dimeric complex anion [Ta₄S₂₂]^6–. The polysulfide anions are composed of two Ta₂S₁₁ subunits which are linked to Ta₄S₂₂ units via terminal sulfur ligands. The Ta⁵⁺ centers are coordinated by S₂^2– and S^2– ligands according to [(Ta₂(μ₂‐η²,η¹‐S₂)₃(η²‐S₂)(S)₂)₂(μ₂‐η¹,η¹‐S₂)]^6–. Every Ta⁵⁺ ion is surrounded by seven sulfur ions forming a strongly distorted pentagonal bipyramid. In the crystal structure the discrete [Ta₄S₂₂]^6– anions are stacked parallel to the crystallographic b‐axis. The Rb⁺ cations are located between these stacks. Rb₆Ta₄S₂₂ crystallizes in the monoclinic space group P2₁/c (No. 14) with a = 11.8253(9) Å, b = 7.9665(4) Å, c = 19.174(2) Å, β = 104.215(9)°, V = 1751.0(2) ų, Z = 2.     

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).