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DDC: 530 × Has files: Yes × Subject: Crystal structure ×

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Now showing 1 - 10 of 22
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    Synthesis and crystal structure of a one-dimensional chain-like strontium(II) coordination polymer built of N-methyldiethanolamine and isobutyrate ligands
    (Chester : International Union of Crystallography, 2021) Seiss, Maximilian; Schmitz, Sebastian; Börner, Martin; Monakhov, Kirill Yu.
    The one-dimensional coordination polymer (I) [Sr(ib)2 (H2mda)]n (Hib = isobutyric acid, C4H8O2, and H2mda = N-methyldiethanolamine, C5H13NO2), namely, catena-poly[[(N-methyldiethanolamine-k3O, N, O')strontium(II)]-di-μ2- isobutyrato-K3O, O':O;K3O:O, O'], was prepared by the one-pot aerobic reaction of [Zr6O4 (OH)4 (ib)12 (H2O)].3Hib with Sr(NO3)2 and H2mda in the presence of MnCl2 and Et3N in acetonitrile. The use of MnCl2 is key to the isolation of I as high-quality colorless crystals in good yield. The molecular solid-state structure of I was determined by single-crystal X-ray diffraction. Compound I crystallizes in the monoclinic space group P21/c and shows a one-dimensional polymeric chain structure. Each monomeric unit of this coordination polymer consists of a central SrII ion in the NO8 coordination environment of two deprotonated ib- ligands and one fully protonated H2mda ligand. The C and O atoms of the H2mda ligand were refined as disordered over two sets of sites with site occupancies of 0.619 (3) and 0.381 (3). Compound I shows thermal stability up to 130°C in air. © 2021 International Union of Crystallography. All rights reserved.
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    Crystal structure of (E)-dodec-2-enoic acid
    (Chester : International Union of Crystallography, 2015) Sonneck, Marcel; Peppel, Tim; Spannenberg, Anke; Wohlrab, Sebastian
    The crystal structure of (E)-dodec-2-enoic acid, C12H22O2, an [alpha],[beta]-unsaturated carb­oxy­lic acid with a melting point (295 K) near room temperature, is characterized by carb­oxy­lic acid inversion dimers linked by pairs of O-H...O hydrogen bonds. The carb­oxy­lic acid group and the following three carbon atoms of the chain of the (E)-dodec-2-enoic acid mol­ecule lie almost in one plane (r.m.s. deviation for the four C atoms and two O atoms = 0.012 Å), whereas the remaining carbon atoms of the hydro­carbon chain adopt a nearly fully staggered conformation [moduli of torsion angles vary from 174.01 (13) to 179.97 (13)°].
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    Crystal structure of (E)-undec-2-enoic acid
    (Chester : International Union of Crystallography, 2015) Sonneck, Marcel; Peppel, Tim; Spannenberg, Anke; Wohlrab, Sebastian
    In the mol­ecule of the title low-melting [alpha],[beta]-unsaturated carb­oxy­lic acid, C11H20O2, the least-squares mean line through the octyl chain forms an angle of 60.10 (13)° with the normal to plane of the acrylic acid fragment (r.m.s. deviation = 0.008 Å). In the crystal, centrosymmetrically related mol­ecules are linked by pairs of O-H...O hydrogen bonds into dimers, forming layers parallel to the (041) plane.
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    Crystal structure of di-n-but­yl­bis­([eta]5-penta­methyl­cyclo­penta­dien­yl)hafnium(IV)
    (Chester : International Union of Crystallography, 2015) Arndt, Perdita; Schubert,Kathleen; Burlakov, Vladimir V.; Spannenberg, Anke; Rosenthal, Uwe
    The crystal structure of the title compound, [Hf(C10H15)2(C4H9)2], reveals two independent mol­ecules in the asymmetric unit. The diffraction experiment was performed with a racemically twinned crystal showing a 0.529 (5):0.471 (5) component ratio. Each HfIV atom is coordinated by two penta­methyl­cyclo­penta­dienyl and two n-butyl ligands in a distorted tetra­hedral geometry, with the cyclo­penta­dienyl rings inclined to one another by 45.11 (15) and 45.37 (16)°. In contrast to the isostructural di(n-butyl)bis([eta]5-penta­methyl­cyclo­penta­dien­yl)zirconium(IV) complex with a noticeable difference in the Zr-butyl bonding, the Hf-Cbut­yl bond lengths differ from each other by no more than 0.039 (3) Å.
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    Thermal annealing studies of GeTe-Sb2Te3 alloys with multiple interfaces
    (New York : American Institute of Physics, 2017) Bragaglia, Valeria; Mio, Antonio M.; Calarco, Raffaella
    A high degree of vacancy ordering is obtained by annealing amorphous GeTe-Sb2Te3 (GST) alloys deposited on a crystalline substrate, which acts as a template for the crystallization. Under annealing the material evolves from amorphous to disordered rocksalt, to ordered rocksalt with vacancies arranged into (111) oriented layers, and finally converts into the stable trigonal phase. The role of the interface in respect to the formation of an ordered crystalline phase is studied by comparing the transformation stages of crystalline GST with and without a capping layer. The capping layer offers another crystallization interface, which harms the overall crystalline quality.
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    Crystal structure of bis(η5-cyclopenta-dienyl)(2, 3-diethylbutane-1, 4-diyl)-hafnium(IV)
    (Chester : International Union of Crystallography, 2015) Burlakov, Vladimir V.; Baumann, Wolfgang; Arndt, Perdita; Spannenberg, Anke; Rosenthal, Uwe
    The title compound, [Hf(C5H5)2(C8H16)], proves a structural motif of hafna­cyclo­pentane besides the coordination of two cyclo­penta­dienyl ligands in an [eta]5-fashion. The hafna­cyclo­pentane ring has a twist conformation and is substituted by two ethyl groups in the [beta],[beta]'-positions, which are trans orientated to each other. One cyclo­penta­dienyl ring and one ethyl group are each disordered over two positions with site-occupancy ratios of 0.679 (15):0.321 (15) and 0.702 (18):0.298 (18), respectively.
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    Crystal structure of (E)-hex-2-enoic acid
    (Chester : International Union of Crystallography, 2015) Peppel, Tim; Sonneck, Marcel; Spannenberg, Anke; Wohlrab, Sebastian
    The crystal structure of the title compound, C6H10O2, an [alpha],[beta]-unsaturated carb­oxy­lic acid, displays carb­oxy­lic acid inversion dimers linked by pairs of O-H...O hydrogen bonds. The packing is characterized by layers of acid dimers. All the non-H atoms of the (E)-hex-2-enoic acid mol­ecule lie almost in the same plane (r.m.s. deviation for the non-H atoms = 0.018 Å).
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    Crystal structure of (E)-pent-2-enoic acid
    (Chester : International Union of Crystallography, 2015) Peppel, Tim; Sonneck, Marcel; Spannenberg, Anke; Wohlrab, Sebastian
    The mol­ecule of the title compound, C5H8O2, a low-melting [alpha],[beta]-unsaturated carb­oxy­lic acid, is essentially planar [maximum displacement = 0.0239 (13) Å]. In the crystal, mol­ecules are linked into centrosymmetric dimers via pairs of O-H...O hydrogen bonds.
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    Crystal structure of (1S,2R,4S)-1-[(morpholin-4-yl)-methyl]-4-(prop-1-en-2-yl)cyclohexane-1,2-diol
    (Chester : International Union of Crystallography, 2015) Outouch, Rachid; Oubaassine, Saadia; Ali, Mustapha Ait; El Firdoussi, Larbi; Spannenberg, Anke
    The asymmetric unit of the title compound, C14H25NO3, contains two independent mol­ecules with similar geometry. The morpholine and cyclo­hexane rings of both mol­ecules adopt a chair conformation. Intra­molecular O-H...N hydrogen bonds are observed. In the crystal, mol­ecules are linked by O-H...O hydrogen bonds into chains parallel to the [101] direction. The chains are further connected through C-H...O hydrogen bonds forming undulating layers parallel to the (-101) plane. The absolute configuration was assigned by reference to an unchanging chiral centre in the synthetic procedure.
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    Crystal structure of bis(η5-cyclopenta-dienyl)(1,4-di-tert-butylbuta-1-en-3-yn-1-yl) zirconium(IV) μ2-hydroxido-bis[tris-(pentafluorophenyl) borate]
    (Chester : International Union of Crystallography, 2015) Burlakov, Vladimir V.; Spannenberg, Anke; Arndt, Perdita; Rosenthal, Uwe
    Alkyl zirconocene cations have been of considerable inter­est as reactive species in many polymerization processes. In the crystal structure of the title compound, [Zr(C12H19)(C5H5)2](C36HB2F30O), the [Zr(C5H5)2((t-Bu)C=C(H)-C2(t-Bu))]+ cation displays a buta-1-en-3-yne ligand side-on coordinated to a typical bent zirconocene [centroid(cp)-Zr-centroid(cp) = 131.4 (3)°, Zr-C(buta-1-en-3-yne) = 2.255 (3), 2.597 (3) and 2.452 (2) Å]. In the [HO(B(C6F5)3)2]- anion, intra­molecular O-H...F hydrogen bonds are observed. One tert-butyl group in the complex cation is disordered over two sets of sites with occupancies 0.701(4):0.299(4).