The Cluster Compounds Ag[W6Br14] and Ag2[W6Br14]

The reaction of W₆Br₁₂ with AgBr in evacuated silica tubes (temperature gradient 925 K/915 K) yielded brownish black octahedra of Ag[W₆Br₁₄] ( I ) and yellowish green platelets of Ag₂[W₆Br₁₄] ( II ) both in the low temperature zone. ( I ) crystallizes cubically (Pn3 (no. 201); a = 13.355 Å, Z = 4) and ( II ) monoclinically (P2₁/c (no. 14); a = 9.384 Å, b = 15.383 Å, c = 9.522 Å, β = 117.34°, Z = 2). Both crystal structures contain isolated cluster anions, namely [(W₆Brⁱ₈)Br^a₆]^1– and [(W₆Brⁱ₈)Br^a₆])]^2–, respectively, with the mean distances and angles: ( I ) d(W–W) = 2.648 Å, d(W–Brⁱ) = 2.617 Å, d(W–Br^a) = 2.575 Å, d(Brⁱ…Brⁱ) = 3.700 Å, d(Brⁱ…Br^a) = 3.692 Å, ∠W–Brⁱ–W = 60.78°. ( II ) d(W–W) = 2.633 Å, d(W–Brⁱ) = 2.624 Å, d(W–Br^a) = 2.613 Å, d(Brⁱ…Brⁱ) = 3.710 Å, d(Brⁱ…Br^a) = 3.707 Å, ∠W–Brⁱ–W = 60.23°. The Ag⁺ cations are trigonal antiprismatically coordinated in ( I ) with d(Ag–Br) = 2.855 Å, but distorted trigonally planar in ( II ) with d(Ag–Br) = 2.588–2.672 Å. The structural details of hitherto known compounds with [W₆Br₁₄] anions will be discussed.     

Two New Modifications of [P(C6H5)4]2[Cu2I4]

Single crystals of two new modifications of [P(C₆H₅)₄]₂[Cu₂I₄] were obtained by reaction of granulated copper with iodine and [P(C₆H₅)₄]I in dry acetone under nitrogen atmosphere. They crystallise monoclinically, space group P2₁/n (No. 14), a = 11.550(6), b = 7.236(2), c = 27.232(13) Å, β = 98.13(3)°, V = 2253(2) ų, and Z = 2 ([P(C₆H₅)₄]₂[Cu₂I₄]-C), and space group Cc (No. 9), a = 17.133(5), b = 15.941(5), c = 18.762 (6) Å, β = 114.02(1)°, V = 4681(3) ų, and Z = 4 ([P(C₆H₅)₄]₂[Cu₂I₄]-D), respectively. In these compounds the [CuI₂]^? anions form dimers di-μ-iodo-diiodocuprate(I), which are either planar ( C ) or folded ( D ).     

Pr10[Si10−xAlxO9+xN17−x]Cl with x ≈ 1 – an Oxonitridoaluminosilicate Chloride

The oxonitridoaluminosilicate chloride Pr₁₀[Si_10?xAl_xO_9+xN_17?x]Cl was obtained by the reaction of praseodymium metal, the respective chloride, AlN and Al(OH)₃ with “Si(NH)₂” in a radiofrequency furnace at temperatures around 1900 °C. The crystal structure was determined by single‐crystal X‐ray diffraction (Pbam, no. 55, Z = 2,a = 10.5973(8) Å, b = 11.1687(6) Å, c = 11.6179(7) Å, R1 = 0.0337). The sialon crystallizes isotypically to the oxonitridosilicate halides Ce₁₀[Si₁₀O₉N₁₇]Br, Nd₁₀[Si₁₀O₉N₁₇]Br and Nd₁₀[Si₁₀O₉N₁₇]Cl, which represent a new layered structure type. The structure refinement was performed utilizing an O/N‐distribution model according to Paulings rules, i.e. nitrogen was positioned on all bridging sites and mixed O/Noccupation was assumed on the terminal sites resulting in charge neutrality of the compounds. The Si and Al atoms were refined equally distributed on their three crystallographic sites, due to their poor distinguishability by X‐ray analysis. The tetrahedra layers of the structure consist of condensed [(Si,Al)N₂(O,N)₂] and [(Si,Al)N₃(O,N)] tetrahedra of Q² and Q³ type. The chemical composition of the compound was derived from electron probe micro analyses (EPMA).     

(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.     

Synthesis and Structural Characterization of the Helical Coordination Polymers [Co(phen)(oba)(H2O)2] and [Cd3(phen)3(oba)2(Hoba)2(H2O)2] (phen = 1, 10‐phenanthroline; oba = 4, 4′‐oxybis(benzoate)

Two coordination polymers, [Co(phen)(oba)(H₂O)₂] ( 1 ) and [Cd₃(phen)₃(oba)₂(Hoba)₂(H₂O)₂] ( 2 ) (oba = 4, 4′‐oxybis(benzoate), phen = 1, 10‐phenanthroline) have been synthesized under hydrothermal conditions. Complex 1 crystallizes in monoclinic, P2₁/n, a = 7.543(6), b = 33.05(2), c = 9.902(5)Å, β = 103.69(2)°, V = 2398(3)ų, Z = 4; 2 in monoclinic, P2/n, a = 15.11(1), b = 10.069(8), c = 28.02(2)Å, β = 101.83(1)°, V = 4174(5)ų, Z = 2. X‐ray single‐crystal diffraction investigations shows that the complexes 1 and 2 consist of helical chains, which are further assembled into layers and networks via supramolecular interactions such as π—π stacking interactions and hydrogen bonds, respectively. The results indicate that the coordination environment is one of the most important factors for assembly of single‐stranded helical chains into double‐stranded helical chains via supramolecular interactions.     

Synthesis,Crystal Structure,and Magnetic Properties of (2,2′‐dipyridylamine)(X−) Copper(II) Complexes (X−: Cyanate,Dicyanamide, Acetate,Thiocyanato)

The synthesis, structure, and magnetic properties of four 2,2′‐dipyridylamine ligand (abbreviated as Hdpa) containing copper(II) complexes. There is one binuclear compound, which is [Cu₂(μ_1,1‐NCO)₂(NCO)₂(Hdpa)₂] ( 1 ), and three mononuclear compounds, which are [Cu{N(CN)₂}₂(Hdpa)₂] ( 2 ), [Cu(CH₃CO₂)(Hdpa)₂·N(CN)₂] ( 3 ), and [Cu(NCS)(Acac)] ( 4 ). Compounds 1 and 4 crystallize in the monoclinic system, space group P2(1)/c and Z = 4, with a = 8.2465(6) Å, b = 9.3059(7) Å, c = 16.0817(12) Å, β = 91.090(1)°, and V = 1233.90(16) ų for 1 and a = 7.6766(6) Å, b = 21.888(3) Å, c = 10.4678(12) Å, β = 90.301(2)°, and V= 1758.8(4) ų for 4 . Compounds 2 and 3 crystallize in the triclinic system, space group P‐1 and Z = 1, with a = 8.1140(3) Å, b = 8.2470(3) Å, c = 9.3120(4) Å, β = 102.2370(10)°, and V = 592.63(4) ų for 2 and a = 7.4780(2) Å, b = 12.5700(3) Å, c = 13.0450(3) Å, β = 96.351(2)°, and V = 1211.17(5) ų for 3 . Complex ( 1 ), the magnetic data was fitted by the Bleaney‐Bowers equation (1). A very good fit was derived with J = 23.96, Θ = ?1.5 (g = 1.97). Complex ( 1 ) shows the ferromagnetism. Complexes ( 2 ), ( 3 ) and ( 4 ) of have the it is the typical paramagnetic behavior of unpaired electrons. Under a low temperature around 25 K, complexes ( 2 ) and ( 3 ) show weak ferromagnetic behavior. They are the cause of hydrogen bonds.     

Li4Ca3Si2N6 and Li4Sr3Si2N6 – Quaternary Lithium Nitridosilicates with Isolated [Si2N6]10– Ions

The isotypic nitridosilicates Li₄Ca₃Si₂N₆ and Li₄Sr₃Si₂N₆ were synthesized by reaction of strontium or calcium with Si(NH)₂ and additional excess of Li₃N in weld shut tantalum ampoules. The crystal structure, which has been solved by single‐crystal X‐ray diffraction (Li₄Sr₃Si₂N₆: C2/m, Z = 2, a = 6.1268(12), b = 9.6866(19), c = 6.2200(12) Å, β = 90.24(3)°, wR₂ = 0.0903) is made up from isolated [Si₂N₆]^10– ions and is isotypic to Li₄Sr₃Ge₂N₆. The bonding angels and distances within the edge‐sharing [Si₂N₆]^10– double‐tetrahedra are strongly dependent on the lewis acidity of the counterions. This finding is discussed in relation to the compounds Ca₅Si₂N₆ and Ba₅Si₂N₆, which also exhibit isolated [Si₂N₆]^10– ions.     

Neue Hexachalcogeno‐Hypodiphosphate der Erdalkalimetalle und des Europiums

New Hexachalcogeno‐Hypodiphosphates of Alkaline‐Earth Metals and Europium Six hexathio‐ and hexaseleno‐hypodiphosphates respectively with the formula M₂P₂X₆ (M = Ca, Sr, Eu, Ba; X = S, Se) were prepared by heating the elements at 750 °C (60 h) and their crystal structures were determined by single crystal X‐ray methods. Eu₂P₂S₆ (a = 9.396(2), b = 7.531(2), c = 6.593(2) Å, β = 91.48(2) °), Ba₂P₂S₆ (a = 9.966(1), b = 7.580(2), c = 6.737(2) Å, β = 91.17(3) °), Ca₂P₂Se₆ (a = 9.664(2), b = 7.519(2), c = 6.859(1) Å, β = 92.02(3) °), Sr₂P₂Se₆ (a = 9.844(2), b = 7.788(2), c = 6.963(1) Å, β = 91.50(3) °), Eu₂P₂Se₆ (a = 9.779(2), b = 7.793(2), c = 6.957(1) Å, β = 91.29(3) °), and Ba₂P₂Se₆ (a = 10.355(2), b = 7.862(2), c = 7.046(1) Å, β = 90.83(3) °) are isotypic and crystallize in the high temperature form of Sn₂P₂S₆ (P2₁/n; Z = 2). The discrete ethanlike (P₂X₆)^4— anions in staggered conformation are linked via X—M—X bonds to a three‐dimensional structure and in the course of this Ca²⁺, Sr²⁺, and Eu²⁺ are coordinated by 8 and Ba²⁺ by 8+1 S and Se atoms respectively. Susceptibility measurements of Eu₂P₂S₆ from 2 K to room temperature show Curie‐Weiss behavior with an experimental magnetic moment of 7.43(2) μ_B/Eu. No magnetic ordering was observed down to 2 K. A ¹⁵¹Eu Mössbauer spectrum at 77 K shows only one signal at an isomer shift of δ = —12.6(1) mm/s. The europium atoms in Eu₂P₂S₆ are therefore in a stable divalent oxidation state.     

Protonation and Hydrogen Atom Abstraction Reactions in the Synthesis of the [HP7M(CO)3]2– Ions (M = Cr,W)

Ethylenediamine (en) solutions of [P₇M(CO)₃]^3– (M = Cr, W) react with weak acids to give [HP₇M(CO)₃]^2– ions where M = Cr ( 4 a ) and W ( 4 b ) in high yields. Competition studies with known acids revealed a pK_a range for 4 b in DMSO of 17.9 to 22.6. The [P₇M(CO)₃]^3– complexes also react with one-half equivalent of I₂ to give 4 through an oxidation/hydrogen atom abstraction process. Labeling studies show that the abstracted hydrogen originates from the [K(2,2,2-crypt)]⁺ ions or from the solvent (DMSO-d₆) in the absence of [K(2,2,2-crypt)]⁺ or other good hydrogen atom donors. In the solid state, the ions have no crystallographic symmetry but in solution they show virtual C_s symmetry (³¹P NMR spectroscopy) due to an intramolecular wagging process. Crystallographic data for [K(2,2,2-crypt)]₂[HP₇W(CO)₃]: triclinic, P 1, a = 10.9709(8) Å, b = 13.9116(10) Å, c = 19.6400(14) Å, α = 92.435(6)°, β = 93.856(6)°, γ = 108.413(6)°, V = 2831.2(4) ų, Z = 2, R(F) = 7.65%, R(wF²) = 14.17% for all 7400 reflections. For [K(2,2,2-crypt)]₂[HP₇Cr(CO)₃]: triclinic, P 1, a = 12.000(3) Å, b = 14.795(3) Å, c = 17.421(4) Å, α = 93.01(2)°, β = 93.79(2)°, γ = 110.72(2)°, V = 2877(2) ų, Z = 2.     

Na6Si2O7 – The Missing Structural Link among Alkali Pyrosilicates

The crystal structure of sodium pyrosilicate (Na₆Si₂O₇) was solved from single crystal diffraction data and refined to an R index of 0.051 for 17034 independent reflections. The compound is triclinic with space group P (a = 5.8007(8) Å, b = 11.5811(15) Å, c = 23.157(3) Å, α = 89.709(10)°, β = 88.915(11)°, γ = 89.004(11)°, V = 1555.1(4) Å³, Z = 8, D_x = 2.615 g · cm^–3, μ(Mo‐K_α) = 7.94 cm^–1). A characteristic feature of the crystals is a twinning by reticular pseudo‐merohedry, which simulates a much larger monoclinic C centered lattice (V′ = 6220 Å³, Z = 32). The twin element corresponds to a twofold rotation axis running parallel to the [0 direction of the triclinic cell. The compound belongs to the group of sorosilicates, i.e. it is based on [Si₂O₇] groups, which are arranged in layers parallel to (100). Charge compensation within the structure is accomplished by monovalent sodium cations distributed among 24 crystallographically independent positions. They are coordinated by four to six nearest oxygen neighbors. Most of the coordination polyhedra can be approximately described as distorted tetrahedra or tetragonal pyramids. An alternative understanding of Na₆Si₂O₇ can be gained if the tetrahedrally coordinated sodium atoms are considered for the construction of a framework. Actually, each four of the dimers within a single slice are linked by a more or less distorted [NaO₄] tetrahedron. The resulting structural motif is similar to the one that can be observed in melilites, where linkage between the T₂O₇ (T: Al, Si) moieties is provided by [MgO₄]‐ (as in akermanite, Ca₂Mg[Si₂O₇]) or [AlO₄] tetrahedra (as in gehlenite, Ca₂Al[AlSiO₇]). By sharing common edges, the [NaO₄] tetrahedra in Na₆Si₂O₇ are forming columns running parallel to 25 . The resulting framework contains tunnels in which the more irregularly coordinated sodium cations are incorporated.     

Synthesis,Structures, Fluorescence Properties,and Natural Bond Orbital (NBO) Analysis of Two Metal [EuIII,CoII] Coordination Polymers Containing 1, 3‐Benzenedicarboxylate and 2‐(4‐methoxyphenyl)‐1H‐imidazo[4, 5‐f][1, 10]phenanthroline Ligands

Two new metal‐organic coordination polymers[Eu(m‐BDC)_1.5(MOPIP) · 1/2H₂O]_n ( 1 ) and [Co(m‐BDC)(MOPIP)₂ · 2H₂O]_n ( 2 ) [m‐H₂BDC = benzene‐1, 3‐dicarboxylic acid, MOPIP = 2‐(4‐methoxyphenyl)‐1H‐imidazo[4, 5‐f] 1 , 10 phenanthroline] were hydrothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. The coordination polymers crystallize in monoclinic space group P2₁/m for 1 ( 2 : P2₁/n), with a = 9.779(2), b = 18.242(4), c = 17.146(3) Å, β = 106.41(3)° for 1 , and with a = 8.2153(16), b = 27.974(6), c = 17.974(4) Å, β = 100.40(3)° for 2 . The crystal structure of complex 1 is a zipper‐like chain of octacoordinate Eu³⁺ ions, in which Eu³⁺ ions are bridged in two coordination modes by m‐BDC²⁺ ligands and decorated by MOPIP ligands. The molecular structure of complex 2 consists of a hexacoordinte Co²⁺ atom, which generates a slightly distorted octahedral arrangement, and assembles into three‐dimensional supramolecular nets by π ··· π stacking interactions. Additionally, these two compounds show strong fluorescence in the solid state at room temperature. Natural bond orbital (NBO) analysis is performed by using the NBO method built in Gaussian 03 Program. The calculation results show a weak covalent interaction between the coordinated atoms and metal ions.     

The Metallic Zintl Phase Ba3Si4 – Synthesis,Crystal Structure,Chemical Bonding,and Physical Properties

The Zintl phase Ba₃Si₄ has been synthesized from the elements at 1273 K as a single phase. No homogeneity range has been found. The compound decomposes peritectically at 1307(5) K to BaSi₂ and melt. The butterfly‐shaped Si₄⁶⁻ Zintl anion in the crystal structure of Ba₃Si₄ (Pearson symbol tP28, space group P4₂/mnm, a = 8.5233(3) Å, c = 11.8322(6) Å) shows only slightly different Si‐Si bond lengths of d(Si–Si) = 2.4183(6) Å (1×) and 2.4254(3) Å (4×). The compound is diamagnetic with χ ≈ −50 × 10⁻⁶ cm³ mol⁻¹. DC resistivity measurements show a high electrical resistivity (ρ(300 K) ≈ 1.2 × 10⁻³ Ω m) with positive temperature gradient dρ/dT. The temperature dependence of the isotropic signal shift and the spin‐lattice relaxation times in ²⁹Si NMR spectroscopy confirms the metallic behavior. The experimental results are in accordance with the calculated electronic band structure, which indicates a metal with a low density of states at the Fermi level. The electron localization function (ELF) is used for analysis of chemical bonding. The reaction of solid Ba₃Si₄ with gaseous HCl leads to the oxidation of the Si₄⁶⁻ Zintl anion and yields nanoporous silicon.     

Synthesis,Structure and Magnetism of Bis[1,2,4‐tris(trimethylsilyl)cyclopentadienyl]europium

Bis[tris(trimethylsilyl)cyclopentadienyl]europium, Eu{C₅H₂[Si(CH₃)₃]₃}₂ (1) , has been synthesized by a modified transmetallation route between Tl{C₅H₂[Si(CH₃)₃]₃} and europium powder in toluene. 1 crystallizes in the monoclinic space group C2/c (No. 15) with a = 20.293(5) Å, b = 20.221(5) Å, c = 9.654(2) Å, β = 106.412(5)°, V = 3800.1(15) ų, Z = 4. The unit cell contains monomeric molecules that adopt a bent metallocene conformation with two partially staggered Cp? ligands. Magnetic susceptibility measurements in the temperature range 2–300 K display ideal Curie paramagnetic behaviour of the 4f⁷ system with Curie constant C = 9.6 × 10^?5 m³ K mol^?1 corresponding to temperature independent μ_eff = 7.8.     

Hydroxo‐bridged Tetranuclear CuII Complexes: {[Cu(bpy)(OH)]4Cl2}Cl2 · 6 H2O and {[Cu(phen)(OH)]4(H2O)2}]Cl4 · 4 H2O

The blue tetranuclear Cu^II complexes {[Cu(bpy)(OH)]₄Cl₂}Cl₂ · 6 H₂O ( 1 ) and {[Cu(phen)(OH)]₄(H₂O)₂}Cl₄ · 4 H₂O ( 2 ) were synthesized and characterized by single crystal X‐ray diffraction. ( 1 ): P 1 (no. 2), a = 9.240(1) Å, b = 10.366(2) Å, c = 12.973(2) Å, α = 85.76(1)°, β = 75.94(1)°, γ = 72.94(1)°, V = 1152.2(4) ų, Z = 1; ( 2 ): P 1 (no. 2), a = 9.770(3) Å, b = 10.118(3) Å, c = 14.258(4) Å, α = 83.72(2)°, β = 70.31(1)°, γ = 70.63(1)°, V = 1252.0(9) ų, Z = 1. The building units are centrosymmetric tetranuclear {[Cu(bpy)(OH)]₄Cl₂}²⁺ and {[Cu(phen)(OH)]₄(H₂O)₂}⁴⁺ complex cations formed by condensation of four elongated square pyramids CuN₂(OH)₂L^ap with the apical ligands L^ap = Cl, H₂O, OH. The resulting [Cu₄(μ₂‐OH)₂(μ₃‐OH)₂] core has the shape of a zigzag band of three Cu₂(OH)₂ squares. The cations exhibit intramolecular and intermolecular π‐π stacking interactions and the latter form 2D layers with the non‐bonded Cl^– anions and H₂O molecules in between (bond lengths: Cu–N = 1.995–2.038 Å; Cu–O = 1.927–1.982 Å; Cu–Cl^ap = 2.563; Cu–O^ap(OH) = 2.334–2.369 Å; Cu–O^ap(H₂O) = 2.256 Å). The Cu…Cu distances of about 2.93 Å do not indicate direct interactions, but the strongly reduced magnetic moment of about 2.74 B.M. corresponds with only two unpaired electrons per formula unit of 1 (1.37 B.M./Cu) and obviously results from intramolecular spin couplings (χ_m(T‐θ) = 0.933 cm³ · mol^–1 · K with θ = –0.7 K).     

Die neuen Schichtsilicate Ba3Si6O9N4 und Eu3Si6O9N4

The New Layer‐Silicates Ba₃Si₆O₉N₄ and Eu₃Si₆O₉N₄ The new oxonitridosilicate Ba₃Si₆O₉N₄ has been synthesized in a radiofrequency furnace starting from BaCO₃, amorphous SiO₂ and Si₃N₄. The reaction temperature was at about 1370 °C. The structure of the colorless compound has been determined by single‐crystal X‐ray diffraction analysis (Ba₃Si₆O₉N₄, space group P3 (no. 143), a = 724.9(1) pm, c = 678.4(2) pm, V = 308.69(9)· 10⁶ pm³, Z = 1, R1 = 0.0309, 1312 independent reflections, 68 refined parameters). The compound is built up of corner sharing SiO₂N₂ tetrahedra forming corrugated layers between which the Ba²⁺ ions are located. Substitution of barium by europium leads to the isotypic compound Eu₃Si₆O₉N₄. Because no single‐crystals could be obtained, a Rietveld refinement of the powder diffractogram was conducted for the structure refinement (Eu₃Si₆O₉N₄, space group P3 (no. 143), a = 711.49(1) pm, c = 656.64(2) pm, V = 287.866(8) ·10⁶ pm³, R_p = 0.0379, R_F² = 0.0638). The ²⁹Si MAS‐NMR spectrum of Ba₃Si₆O₉N₄ shows two resonances at ?64.1 and ?66.0 ppm confirming two different crystallographic Si sites.     

Two Succinato‐bridged Zinc(II) Phenanthroline Complexes: [Zn(phen)L2/2](H2L) and [(phen)2Zn(μ‐L)Zn(phen)2]L � 11H2O with H2L = Succinic Acid

Two mixed ligand Zn^II complexes [Zn(phen)L_2/2](H₂L) ( 1 ) and [(phen)₂Zn(μ‐L)Zn(phen)₂]L � 11H₂O ( 2 ) with H₂L = suc‐cinic acid were prepared and crystallographically characterized. Complex 1 crystallizes in the monoclinic space group C2/c (no. 15) with a = 13.618(1) Å, b = 9.585(1) Å, c = 15.165(1) Å, β = 96.780(6)°, V = 1965.6(3)ų, Z = 4 and complex 2 in the triclinic space group P 1¯ (no. 2) with a = 12.989(2)Å, b = 14.464(2)Å, c = 18.025(3)Å, α = 90.01(1)°, β = 109.69(1)°, γ = 112.32(1)°, V = 2917.4(8) ų, Z = 2. 1 consists of succinic acid molecules and 1D zigzag [Zn(phen)(C₄H₄O₄)_2/2] polymeric chains, in which the tetrahedrally coordinated Zn atoms are bridged by bis ‐ monodentate succinato ligands. Succinic acid molecules play an important role in supramolecular assemblies of the polymeric chains into 2D layers as well as in the stacking of 2D layers. 2 is composed of [(phen)₂Zn(μ‐L)Zn(phen)₂]²⁺ complex cations, succinate anions and hydrogen bonded water molecules. Within the divalent cations, Zn atoms are octahedrally coordinated by four N atoms of two phen ligands and two O atoms of one bis‐chelating succinato ligand. Through the intermolecular π—π stacking interactions, the complex cations form positively charged 2D layers, between which the noncoordinating succinate anions and water molecules are sandwiched.     

Diversity of Strontium Nitridogermanates(IV): Novel Sr4[GeN4], Sr8Ge2[GeN4], and Sr17Ge2[GeN3]2[GeN4]2

Single crystals of three new strontium nitridogermanates(IV) were grown in sealed niobium ampules from sodium flux. Dark red Sr₄[GeN₄] crystallizes in space group P2₁/c with a = 9.7923(2) Å, b = 6.3990(1) Å, c = 11.6924(3) Å and β = 115.966(1)°. Black Sr₈Ge₂[GeN₄] contains Ge^4– anions coexisting with [Ge^IVN₄]^8– tetrahedra and adopts space group Cc with a = 10.1117(4) Å, b = 17.1073(7) Å, c = 10.0473(4) Å and β = 115.966(1)°. Black Sr₁₇Ge₆N₁₄ features the same anions alongside trigonal planar [Ge^IVN₃]^5– units. It crystallizes in P1 with a = 7.5392(1) Å, b = 9.7502(2) Å, c = 11.6761(2) Å, α = 103.308(1)°, β = 94.651(1)° and γ = 110.248(1)°.     

3Mg(OH)2·MgSO4·8H2O: A Metastable Phase in the System Mg(OH)2‐MgSO4‐H2O

In the course of investigations relating to magnesia oxysulfate cement the basic magnesium salt hydrate 3Mg(OH)₂ · MgSO₄ · 8H₂O (3–1–8 phase) was found as a metastable phase in the system Mg(OH)₂‐MgSO₄‐H₂O at room temperature (the 5–1–2 phase is the stable phase) and was characterized by thermal analysis, Raman spectroscopy, and X‐ray powder diffraction. The complex crystal structure of the 3–1–8 phase was determined from high resolution laboratory X‐ray powder diffraction data [space group C2/c, Z = 4, a = 7.8956(1) Å, b = 9.8302(2) Å, c = 20.1769(2) Å, β = 96.2147(16)°, and V = 1556.84(4) ų]. In the crystal structure of the 3–1–8 phase, parallel double chains of edge‐linked distorted Mg(OH₂)₂(OH)₄ octahedra run along [–110] and [110] direction forming a pattern of crossed rods. Isolated SO₄ tetrahedra and interstitial water molecules separate the stacks of parallel double chains.     

Das SCN–-Ion als ambidenter Ligand – Synthese und Kristallstrukturen von (Bu4N)4[Ag2Fe2(SCN)12] und (Et4N)2 [Ag2Fe(SCN)6]

The SCN^– Ion as an Ambidentate Ligand – Synthesis and Crystal Structures of (Bu₄N)₄[Ag₂Fe₂(SCN)₁₂] and (Et₄N)₂ [Ag₂Fe(SCN)₆] In (Bu₄N)₄[Ag₂Fe₂(SCN)₁₂] · 2 CH₃NO₂ ( 1 ) and (Et₄N)₂[Ag₂Fe(SCN)₆] ( 2 ) the ambidentate SCN^– anions link Ag⁺ with Fe³⁺ and Fe²⁺ centers, respectively. The tetranuclear anions in 1 are built from [Fe(NCS)₆]^3– groups connected by Ag⁺ ions. In 2 the same bridging pattern leads to polymeric anionic chains containing [Fe(NCS)₆]^4– groups linked by Ag⁺ ions. (Bu₄N)₄[Ag₂Fe₂(SCN)₁₂] · 2 CH₃NO₂ ( 1 ): a = 1184.10(10), b = 1370.80(10), c = 1776.5(2) pm, α = 99.090(10), β = 102.100(10), γ = 100.360(10)°, V = 2715.5(4) · 10⁶ pm³, space group P1; (Et₄N)₂[Ag₂Fe(SCN)₆] ( 2 ): a = 1607.0(2), b = 1006.92(9), c = 1096.13(9) pm, V = 1773.7(3) · 10⁶ pm³, space group Pnnm.     

Über Thallium(I)-chlorooxomolybdate: Synthese und Kristallstrukturen von Tl[MoOCl4(NCCH3)], Tl[Mo2O2Cl7] und Tl2[Mo4O4Cl14] und die Struktur von Tl2[MoCl6]

On Thallium(I)-oxochloromolybdates: Synthesis and Crystal Structures of Tl[MoOCl₄(NCCH₃)], Tl[Mo₂O₂Cl₇], and Tl₂[Mo₄O₄Cl₁₄] and the Structure of Tl₂[MoCl₆] Black crystals of Tl₂[MoCl₆] are formed in the reaction of TlCl with MoOCl₃ in a sealed evacuated glass ampoule at 350 °C. The crystal structure analysis shows that Tl₂[MoCl₆] (cubic, Fm 3¯m, a = 986.35(7) pm) adopts the K₂[PtCl₆] structure with a Mo–Cl bond length of 236.6 pm. Tl[MoOCl₄(NCCH₃)] was obtained by the reaction of TlCl with MoOCl₃ in acetonitrile in form of yellow, moisture sensitive crystals. The structure (orthorhombic, Cmcm, a = 746.0(1), b = 1463.8(3), c = 857.3(2) pm) is built of Tl⁺ cations and octahedral [MoOCl₄(NCCH₃)]^– anions in which the acetonitrile ligand is bound in trans position to the oxygen. The reaction of TlCl and MoOCl₃ in dichloromethane yields Tl[Mo₂O₂Cl₇] and Tl₂[Mo₄O₄Cl₁₄] as green moisture sensitive crystals. The structure of Tl[Mo₂O₂Cl₇] (orthorhombic, Pmmn, a = 694.3(1), b = 951.9(2), c = 904.7(1) pm) consists of Tl⁺ cations and dinuclear [Mo₂O₂Cl₇]^– anions, with two equidistant chlorine bridges of 248.2 and one longer chlorine bridge of 265.7 pm. The oxygen atoms are located in the trans positions of the longer chloro bridge. The structure of Tl₂[Mo₄O₄Cl₁₄] (triclinic, P1¯, a = 692.8(1), b = 919.6(1), c = 998.9(1) pm, α = 104.94(1)°, β = 90.31(1)°, γ = 108.14(1)°) is build of Tl⁺ cations and [Mo₄O₄Cl₁₄]^2– anions which form tetramers of distorted octahedral, edgesharing (MoOCl₅) units with chlorine atoms in the bridging positions. The oxygen atoms are located in the trans positions of the longest chlorine bridges.