Triäthanolaminkomplexe. II. Die Kristallstruktur von 2 ZnCl2 · C6H15O3N · H2O

The crystal structure of 2 ZnCl₂ · C₆H₁₅O₃N · H₂O has been determined by direct methods. The triethanolamine complex crystallizes in space group P 2₁/c with a₀ = 10.86, b₀ = 10.08, c₀ = 14.09 Å, β = 93.5° und Z = 4. The structure has been refined by least squares methods. Final R₁ index is 4.4% for 579 reflexions. One half of the zinc atoms are octahedrally coordinated by a chlorine atom, a water molecule and by the nitrogen and the three oxygen of the triethanolamine molecule. The other half is tetrahedrally surrounded by chlorine. The two zinc complexes are connected via a common chlorine atom.     

Metall-Schwefelstickstoff-Verbindungen. 17. Die Verbindungen HgN2S · NH3 und 2Hg(NH3)2I2 · S4N4

Metal Sulphur Nitrogen Compounds. 17. Compounds HgN₂S · NH₃ and Hg(NH₃)₂I₂ · S₄N₄ The crystal and molecular structures of the known compounds HgN₂S · NH₃ and of the new inclusion compound 2Hg(NH₃)₂I₂ · S₄N₄ are reported. HgN₂S · NH₃ is orthorhombic, space group Pbca with a = 5.548, b = 10.158, c = 14.919 Å, Z = 8. In the dimeric molecules two Hg atoms are bridged to form eight-membered rings . In addition, each Hg is coordinated by an NH₃ molecule and by an N atom of an adjacent ring. This results in a two-dimensional network. 2Hg(NH₃)₂I₂ · S₄N₄ is tetragonal, space group P4₂/nmc, a = 8.948, c = 13.188 Å, Z = 2. It is an inclusion compound with S₄N₄ molecules in the holes of the lattice of the large Hg(NH₃)₂I₂ tetrahedra.     

Einkristallzüchtung und Röntgenstrukturanalyse von CoSO4 · Pyrazin · 6 H2O (I) und (CoSO4)2 · Pyrazin · 12 H2O (II)

Crystal Growth and Structure of CoSO₄ · Pyrazine · 6 H₂O (I) and (CoSO₄)₂ · Pyrazine · 12 H₂O (II) Single crystals of μ-pyrazino-bis[pentaquacobalt(II)]-sulfate-dihydrate CoSO₄(pz) · 6 H₂O and Tetraqua-μ-pyrazino-cobalt(II)sulfate-dihydrate (CoSO₄)₂(pz) · 12 H₂O were grown by using gel methods and investigated by X-ray analysis. CoSO₄(pz) · 6 H₂O (I) shows monoclinic symmetry, space group C2/c; a = 1006.4(4) pm, b = 1026.9(4) pm, c = 1261.5(2) pm; β = 104.01(4)°; Z = 4. (CoSO₄)₂(pz) · 12 H₂O (II) shows orthorhombic symmetry, space group Pbam; a = 1262.3(4) pm, b = 1231.3(4) pm, c = 684.1(2) pm; Z = 2. CoSO₄ and Pyrazine crystallize in a polymeric (I) as well as in a dimeric (II) compound. In the polymeric compound the molecules are bonded by pyrazine to form alternating linear chains. The dimer is a dinuclear complex with a bridging pyrazine molecule.     

Co0.50VOPO4·2H2O

The crystal structure of cobalt vanadophosphate dihydrate {systematic name: poly[diaqua‐μ‐oxido‐μ‐phosphato‐hemicobalt(II)vanadium(II)]}, Co_0.50VOPO₄·2H₂O, shows a three‐dimensional framework assembled from VO₅ square pyramids, PO₄ tetrahedra and Co[O₂(H₂O)₄] octahedra. The Co^II ions have local 4/m symmetry, with the equatorial water molecules in the mirror plane, while the V and apical O atom of the vanadyl group are located on the fourfold rotation axis and the P atoms reside on sites. The PO₄ tetrahedra connect the VO₅ polyhedra to form a planar P–V–O layer. The [Co(H₂O)₄]²⁺ cations link adjacent P–V–O layers via vanadyl O atoms to generate an unprecedented three‐dimensional open framework. Powder diffraction measurements reveal that the framework collapses on removal of the water molecules.     

Structural and Dynamic Study of SnCl4 · 2 Me2O and SnCl4 · 2 Me2Se Preliminary communication

The solid cis-SnCl₄ · 2Me₂O and trans-SnCl₄ · 2Me₂Se adducts have been synthesised and characterised by IR. and Raman spectroscopy. NMR. and vibrational spectroscopy show a fast cis-trans equilibrium for both complexes in solution in an inert solvent.     

Die KristallStruktur von LiAlCl4 · 3 SO2

Crystal Structure of LiAlCl₄ · 3 SO₂ Single crystals of LiAlCl₄ · 3SO₂ were grown on a 4-circle diffractometer in a temperature gradient 17°/40°C and diffraction data were collected at ?10°C. The compound crystallizes in the orthorhombic system, space group Pnam (No. 62) with a = 951.6(5), b = 1327.1(9), c = 1017.4(8) pm, Z = 4. The atomic parameters were refined to R = 0.049. The characteristic structural units are parallel strings of the composition Li(SO₂)_6/2. The spaces between these strings are occupied by nearly ideal tetrahedral AlCl₄ ions. The close relationship with the structure of LiClO₄ ·% 3H₂O is discussed.     

Synthese und Kristallstruktur von [WNCl3 · NC–Ph]4 · 3 CH2Cl2

Synthesis and Crystal Structure of [WNCl₃ · NCPh]₄ · 3 CH₂Cl₂ The adduct of tungsten nitride trichloride with benzonitrile, [WNCl₃ · NCPh]₄, is formed by the reaction of N,N,N'-tris(trimethylsilyl)benzamidine and tungsten hexachloride in CCl₄ solution. It forms red crystal needles and was characterized by its IR spectrum and an X-ray crystal structure determination (1983 unique observed reflexions, R = 0.075). Crystal data: a = 1464.8, b = 1902.6, c = 2033.8 pm, β = 102.27°, space group C2/c, Z = 4. In the [WNCl₃ · NCPh]₄ molecule the tungsten atoms were located at the vertices of a square and are linked with one another via linear W?N? W nitrido bridges with alternating short and long bonds having average lengths of 166 and 211 pm. The N atoms of the benzonitrile ligands are in the positions trans to the W?N bonds at distances of 237 pm.     

ChemInform Abstract: 2Mg(OH)2·MgCl2·2H2O and 2Mg(OH)2·MgCl2·4H2O,Two High Temperature Phases of the Magnesia Cement System.

The title materials exist as stable phases in the MgO—MgCl₂—H₂O system at 120 °C.     

Erdalkaliquadratate. IV. SrC4O4 · 3 H2O Typ II

Alkaline Earth Squarates. IV. SrC₄O₄ · 3 H₂O Type II In SrC₄O₄ · 3 H₂O (type II) Sr²⁺ and C₄O₄^2? build up a threedimensional framework. Sr²⁺ is 9-coordinated by three water molecules and six oxygen atoms of the squarate dianions, which form a distorted mono-capped square anti prism. Strong hydrogen bonding has to be assumed between water and that O_squarate which is bound weakly to Sr²⁺. C? C and C? O bond lengths are typical of delocalization of the, π-electron system. Dehydration to SrC₄O₄ · 1 H₂O is reversible. The single crystal nature, however, is destroyed during this process.     

Metall-Schwefelstickstoff-Verbindungen. 16. Reaktionsprodukte von Blei- und Zinnsalzen mit S4N4 Die Strukturen von PbN2S2 · NH3, PbN2S2 und SnCl4 · 2S4N4

Metal Sulfur Nitrogen Compounds. 16. Products of the Reaction of Lead- and Tin Salts with S₄N₄. Structures of PbN₂S₂ · NH₃, PbN₂S₂, and SnCl₄ · 2S₄N₄ PbN₂S₂ · NH₃ is monoclinic, P2₁/a, a = 5.671, b = 16.123, c = 6.102 Å, β = 95.12°, Z = 4, PbN₂S₂, however, orthorhombic, P2₁2₁2₁, a = 4.375, b = 7.654, c = 12.274 Å, Z = 4. The planar five-membered PbN₂S₂ rings in both compounds show no remarkable differences. In PbN₂S₂ · NH₃, the NH₃ molecule is bound to Pb perpendicularly to the plane of the ring. The structure of the long known addition compound SnCl₄ · 2S₄N₄ was determined. It is orthorhombic, Pc2₁b, a = 11.467, b = 11.995, c = 12.374 Å, Z = 4. Sn shows sixfold coordination, the two S₄N₄ rings are attached to Sn trans to each other via a N atom.     

Magnesium chloride tetrahydrate,MgCl2·4H2O

The title compound, MgCl₂·4H₂O, was crystallized at 403 K and its structure determined at 200 K. The structure is built up from MgCl₂(H₂O)₄ octahedra with a trans configuration. Each complex is situated on a crystallographic twofold axis, with the rotation axis aligned along one H₂O—Mg—OH₂ axis. They are connected by a complex network of O—H...Cl hydrogen bonds. The structure contains two‐dimensional sections that are essentially identical to those in the reported tetrahydrates of CrCl₂, FeCl₂, FeBr₂ and CoBr₂, but they are stacked in a different manner in MgCl₂·4H₂O compared with the transition metal structures.     

Earth Alkaline Tetrathiosquarates. II. – Syntheses and Crystal Structures of SrC4S4·4 H2O and Ba4K2(C4S4)5·16 H2O

Concentrated aqueous solutions of strontium chloride and barium chloride, respectively, allow on addition of the potassium salt of tetrathiosquarate, K₂C₄S₄·H₂O, the isolation of the earth alkaline salts SrC₄S₄·4 H₂O ( 1 ) and Ba₄K₂(C₄S₄)₅·16 H₂O ( 2 ), both as dark red crystals. The crystal structure determinations ( 1 : orthorhombic, Pnma, a = 8.149(1), b = 12.907(2), c = 10.790(2) Å, Z = 4; 2 : orthorhombic, Pbca, a = 15.875(3), b = 21.325(5), c = 16.119(1) Å, Z = 4) show the presence of C₄S₄²⁻ ions with only slightly distorted D_4h symmetry having average C–C and C–S bond lengths of 1.41Å and 1.681Å for 1 and 1.450Å and 1.657Å for 2 . The structure of 1 contains concatenated edge‐sharing Sr(H₂O)₆S₂ polyhedra. The Sr²⁺ ions are in eight‐fold coordination with Sr–O distances of 2.50–2.72Å and Sr–S distances of 3.21Å, (C₄S₄)²⁻ acts as a chelating ligand towards Sr²⁺. The structure is closely related to the previously reported Ca²⁺ containing analogue, which is of lower symmetry belonging to the monoclinic crystal system. A supergroup‐subgroup relation between the space groups of both structures is present. The structure of 2 is made up of Ba²⁺ and K⁺ ions in eight and nine‐fold coordination by H₂O molecules and (C₄S₄)²⁻ ions which act as chelating ligands towards one cation and bridging between two cations. The coordination polyhedra of the cations are connected by common edges and corners in two dimensions to layers which are connected by tetrathiosquarate ions to a three‐dimensional network. The infrared and Raman spectra show bands typical for the molecular building units of the two compounds.     

RbCrIII(C2O4)2·2H2O,Cs2Mg(C2O4)2·4H2O and Rb2CuII(C2O4)2·2H2O: three new complex oxalate hydrates

Rubidium chromium(III) dioxalate dihydrate [di­aqua­bis(μ‐oxalato)­chromium(III)­rubidium(I)], [RbCr(C₂O₄)₂(H₂O)₂], (I), and dicaesium magnesium dioxalate tetrahydrate [tetra­aqua­bis(μ‐oxalato)­magnesium(II)­dicaesium(I)], [Cs₂Mg(C₂­O₄)₂(H₂O)₄], (II), have layered structures which are new among double‐metal oxalates. In (I), the Rb and Cr atoms lie on sites with imposed 2/m symmetry and the unique water molecule lies on a mirror plane; in (II), the Mg atom lies on a twofold axis. The two non‐equivalent Cr and Mg atoms both show octahedral coordination, with a mean Cr—O distance of 1.966 Å and a mean Mg—O distance of 2.066 Å. Dirubid­ium copper(II) dioxalate dihydrate [di­aqua­bis(μ‐oxalato)­copper(II)­dirubidium(I)], [Rb₂Cu(C₂O₄)₂(H₂O)₂], (III), is also layered and is isotypic with the previously described K₂‐ and (NH₄)₂Cu^II(C₂O₄)₂·2H₂O compounds. The two non‐equivalent Cu atoms lie on inversion centres and are both (4+2)‐coordinated. Hydro­gen bonds are medium‐strong to weak in the three compounds. The oxalate groups are slightly non‐planar only in the Cs–Mg compound, (II), and are more distinctly non‐planar in the K–Cu compound, (III).     

Studies on julimycins—VI The structures of julichromes Q1·2, Q2·2, Q3·5, Q3·5, Q4·5, Q2·5 and Q5·5

Julichromes Q_1·2 and Q_2·2 are identified as the dehydration products of julimycin B-II. The structures of julichromes, which commonly have a new anthraquinonyl Q₅ unit, are confirmed by their preparation from known julichromes. The conversion reaction, Q₂ → Q₅, which involves an intra-molecular redox is probably concerned in the biosynthesis of this unit.     

Zur Kenntnis der Phase BaO · Al2O3 · 7 H2O

On the Compound BaO · Al₂O₃ · 7 H₂O On the basis of investigations using ²⁷Al, ¹H NMR, IR and thermoanalytical methods for the compound BaO · Al₂O₃ · 7 H₂O a constitution as Ba_n[Al₂(OH)₈]_n · 3n H₂O with condensed AlO₆ groups, sharing edges, is proposed. Relations between the Ba/Al ratio and the constitution of anions of barium aluminate hydrates are discussed.     

The O–H···O, O–H···N and C–H···O hydrogen bonds in 1,4-dimethylpiperazine mono-betaine monohydrate

1,4-Dimethylpiperazine mono-betaine (1-carboxymethyl-1,4-dimethylpiperazinium inner salt, MBPZ) crystallizes as monohydrate. The crystals are orthorhombic, space group Pccn. Two MBPZ molecules and two water molecules form a cyclic oligomer, (MBPZ·H₂O)₂. The O–H···O and O–H···N hydrogen bonds are of 2.769(1) and 2.902(1) Å, respectively. The dimers interact with the neighboring molecules through the C–H···O hydrogen bonds of 3.234(1) Å. The piperazine ring assumes a chair conformation with the N(4)–CH₃ and N⁺(1)–CH₂COO⁻ groups in the equatorial position and the N⁺(1)–CH₃ group in the axial one. The FTIR spectrum is compared with that calculated by the B3LYP/6-31G(d,p) level of theory.     

Hydrate schwacher und starker Basen. XI. Die Kristallstrukturen von NaOH · 3,5H2O und NaOH · 7 H2O. Eine Präzisierung

Hydrates of Weak and Strong Bases. XI. The Crystal Structures of NaOH · 3,5H₂O and NaOH · 7 H₂O. A Refinement The crystal structures of the hydrates NaOH · 3,5 H₂O (space group P2₁/c, Z = 8 formula units per unit cell; lattice parameters: a = 6.481, b = 12.460, c = 11.681 Å, β = 104.12° at ?100°C) and NaOH · 7 H₂O (P2₁/c, Z = 4; a = 7.344, b = 16.356, c = 6.897 Å, β = 92.91° at ?150°C) have been redetermined using MoKα diffractometer data. The obtained refinement of the structures, including the localization also of the H atoms for the first time, has led to new findings with respect to the H bonds. In particular, in both hydrates there is one such interaction of the rare type OH^? …? OH₂, from an OH^? ion to an H₂O molecule, i. e. with the OH^? ion as the proton donor.     

Die Kristall- und MolekülStruktur von S4N4·2C7H8

Crystal and Molecular Structure, of S₄N₄ · 2C₇H₈ The structure of the title compound has been determined from threedimensional X-ray data. Crystals are monoclinic, with unit cell dimenions a = 16.532 Å, b = 8.563 Å, c = 10.880 Å, β = 103.2°, space group C? C2/c and Z = 4. Least squares refinement, by use of 1132 independent reflections measured on a diffractometer has reached 3.9%. In the S₄N₄·2C₇H₈ molecules the organic components are linked to two sulfur atoms of the S₄N₄, ring each.     

复合物HNO···H2O2内N-H···O蓝移氢键的理论研究

A theoretical study on the blue-shifted H-bond N-H…O and red-shifted H-bond O-H…O in the complexHNO…H_2O_2 was conducted by employment of both standard and counterpoise-corrected methods to calculate thegeometric structures and vibrational frequencies at the MP2/6-31G(d),MP2/6-31 G(d,p),MP2/6-311 q G(d,p),B3LYP/6-31G(d),B3LYP/6-31 G(d,p) and B3LYP/6-311 G(d,p) levels.In the H-bond N-H…O,the calcu-lated blue shift of N-H stretching frequency is in the vicinity of 120 cm~(-1) and this is indeed the largest theoreticalestimate of a blue shift in the X-H…Y H-bond ever reported in the literature.From the natural bond orbital analy-sis,the red-shifted H-bond O-H…O can be explained on the basis of the dominant role of the hyperconjugation.For the blue-shifted H-bond N-H…O,the hyperconjugation was inhibited due to the existence of significant elec-tron density redistribution effect,and the large blue shift of the N-H stretching frequency was prominently due tothe rehybridization of sp~n N-H hybrid orbital.