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End date: 2023 × Start date: 2020 × End date: 2019 × Start date: 2010 × DDC: 540 × Type: Text × Subject: Crystal structure ×

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Now showing 1 - 10 of 14
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    Layered manganese bismuth tellurides with GeBi4Te7- and GeBi6Te10-type structures: Towards multifunctional materials
    (London : RSC Publ., 2019) Souchay, Daniel; Nentwig, Markus; Günther, Daniel; Keilholz, Simon; de Boor, Johannes; Zeugner, Alexander; Isaeva, Anna; Ruck, Michael; Wolter, Anja U.B.; Büchnerde, Bernd; Oeckler, Oliver
    The crystal structures of new layered manganese bismuth tellurides with the compositions Mn0.85(3)Bi4.10(2)Te7 and Mn0.73(4)Bi6.18(2)Te10 were determined by single-crystal X-ray diffraction, including the use of microfocused synchrotron radiation. These analyses reveal that the layered structures deviate from the idealized stoichiometry of the 12P-GeBi4Te7 (space group P3m1) and 51R-GeBi6Te10 (space group R3m) structure types they adopt. Modified compositions Mn1-xBi4+2x/3Te7 (x = 0.15-0.2) and Mn1-xBi6+2x/3Te10 (x = 0.19-0.26) assume cation vacancies and lead to homogenous bulk samples as confirmed by Rietveld refinements. Electron diffraction patterns exhibit no diffuse streaks that would indicate stacking disorder. The alternating quintuple-layer [M2Te3] and septuple-layer [M3Te4] slabs (M = mixed occupied by Bi and Mn) with 1 : 1 sequence (12P stacking) in Mn0.85Bi4.10Te7 and 2 : 1 sequence (51R stacking) in Mn0.81Bi6.13Te10 were also observed in HRTEM images. Temperature-dependent powder diffraction and differential scanning calorimetry show that the compounds are high-temperature phases, which are metastable at ambient temperature. Magnetization measurements are in accordance with a MnII oxidation state and point at predominantly ferromagnetic coupling in both compounds. The thermoelectric figures of merit of n-type conducting Mn0.85Bi4.10Te7 and Mn0.81Bi6.13Te10 reach zT = 0.25 at 375 °C and zT = 0.28 at 325 °C, respectively. Although the compounds are metastable, compact ingots exhibit still up to 80% of the main phases after thermoelectric measurements up to 400 °C. © The Royal Society of Chemistry 2019.
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    Crystal structure of bis(pentamethylcyclopentadienyl)-(4,4′-di-tert- butylbipyridyl)hafnium(IV)-hexane (1:0.5), Hf(C10H15) 2(C18H24N2) · 0.5C 6H14
    (Berlin : de Gruyter, 2010) Beweries, T.; Spannenberg, A.; Rosenthal, U.
    C41H61HfN2, monoclinic, P21/n (no. 14), a = 13.4410(4) Å, b = 13.9983(6) Å, c = 21.1996(8) Å, β = 98.144(3)°, V = 3948.5 Å3, Z = 4, Rgt(F) = 0.051, wRref(F2) = 0.121,T = 200 K. © 2014 Oldenbourg Wissenschaftsverlag, München.
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    Crystal structure of 1-bis(((1R,2S,5R)-2-isopropyl-5-methylcyclohexyl) cyclopentadienyl)-1-trimethylphosphine-2,3-bis(trimethylsilyl) -1-hafnacycloprop-2-ene-hexane (1:0.5), (HfC8H18Si 2)(C15H22)2(PC3H 9) · 0.5C6H14
    (Berlin : de Gruyter, 2010) Klahn, M.; Spannenberg, A.; Rosenthal, U.
    C44H78HfPSi2, tetragonal, P4 1212 (no. 92), a = 14.9634(2) Å, c = 44.9270(8) Å, V = 10059.3 Å3, Z = 8, Rgt(F) = 0.026, wRref(F2) = 0.073, T = 200 K. © by Oldenbourg Wissenschaftsverlag, München.
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    Crystal structure of bis(pentamethylcyclopentadienyl)(1-tert- butylisocyanido)-2-trimethylsilyl-3-[(trimethylsilyl)ethynyl]-hafnacyclopropene, (C10H15)2(C5H9N) Hf(C10H18Si2)
    (Berlin : de Gruyter, 2010) Beweries, T.; Spannenberg, A.; Rosenthal, U.
    C35H57HfNSi2, monoclinic, P121/c1 (no. 14), a = 10.7410(3) Å, b = 16.2302(5) Å, c = 21.6945(7) Å, β = 104.512(2)°, V = 3661.3 Å3, Z = 4, R gt(F) = 0.049, wRref(F2) = 0.138, T = 200 K. © 2014 Oldenbourg Wissenschaftsverlag, München.
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    Iodidobis(≠5-penta-methyl-cyclo-penta-dien-yl)titanium(III)
    (Chester : International Union of Crystallography, 2010) Kessler, M.; Spannenberg, A.; Rosenthal, U.
    In the title complex mol-ecule, [Ti(C10H15) 2I], the paramagnetic Ti(III) atom is coordinated by two penta-methyl-cyclo-penta-dienyl (Cp*) ligands and one iodide ligand. The two Cp*ligands are in a staggered orientation. The coordination geometry at the titanium atom can be described as distorted trigonal-planar.
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    Intermolecular hydrogen bonding in isostructural pincer complexes [OH-(t-BuPOCOPt-Bu)MCl] (M = Pd and Pt)
    (Chester : International Union of Crystallography, 2019) Joksch, M.; Spannenberg, A.; Beweries, T.
    In the crystal structure of the isostructural title compounds, namely {2,6-bis[(di-tert-butylphosphanyl)oxy]-4-hydroxyphenyl}chloridopalladium(II), [Pd(C22H39O3P2)Cl], 1, and {2,6-bis[(di-tert-butylphosphanyl)oxy]-4-hydroxyphenyl}chloridoplatinum(II), [Pt(C22H39O3P2)Cl], 2, the metal centres are coordinated in a distorted square-planar fashion by the POCOP pincer fragment and the chloride ligand. Both complexes form strong hydrogen-bonded chain structures through an interaction of the OH group in the 4-position of the aromatic POCOP backbone with the halide ligand.
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    [2,2-Bis(diphenylphosphanyl)propane κ2P,P0] tetracarbonylchromium(0)dichloromethane monosolvate
    (Chester : International Union of Crystallography, 2010) Peulecke, N.; Peitz, S.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.
    The title compound, [Cr(C27H26P2)(CO) 4]·CH2Cl2, was obtained by the reaction of Ph2PCMe2PPh2 with Cr(CO)6 in refluxing toluene by substitution of two carbonyl ligands. The CrC 4P2 coordination geometry at the Cr atom is distorted octa-hedral, with a P - Cr - P bite angle of 70.27 (2)°.
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    (+)-{1,2-Bis[(2R,5R)-2,5-diethyl-phospho-lan-1-yl]ethane- κ2 P,P′}(≠4-cyclo-octa-1,5-diene)rhodium(I) tetra-fluoridoborate
    (Chester : International Union of Crystallography, 2010) Schulz, S.; Fischer, C.; Drexler, H.-J.; Heller, D.
    The title compound, [Rh(C8H12)(C18H 36P2)]BF4, exhibits a rhodium(I) complex cation with a bidentate bis-phosphine ligand and a bidentate 2, 2-coordinated cyclo-octa-1,5-diene ligand. The ligands form a slightly distorted square-planar coordination environment for the Rh(I) atom. An intra-molecular P-Rh-P bite angle of 83.91 (2)° is observed. The dihedral angle between the P - Rh - P and the X - Rh - X planes (X is the centroid of a double bond) is 14.0 (1)°. The BF4 anion is disordered over two positions in a 0.515 (7):0.485 (7) ratio.
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    (tert-Butylimido)bis(η5-cyclopenta-dienyl) pyridinezirconium(IV)
    (Chester : International Union of Crystallography, 2010) Kaleta, K.; Arndt, P.; Spannenberg, A.; Rosenthal, U.
    The title compound, [Zr(C5H5)2(C 4H9N)(C5H5N)], was obtained from the reaction of (C5H5)2Zr(py)(η2- Me3SiC2SiMe3) (py is pyridine) and tBuN=C=NtBu alongside the formation of (C 5H5)2Zr(CNtBu)(2-Me 3SiC2SiMe3). The zirconium atom is coordinated in a distorted tetrahedral geometry by two cyclopentadienyl ligands, a pyridine ligand, and a tertbutylimido ligand via a Zr=N double bond. The tertbutyl group is disordered over two positions in a 0.634 (5):0.366 (5) ratio.
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    [Bis(diphenylphosphanyl)dimethylsilane κ2P,P′] tetracarbonylchromium(0)
    (Chester : International Union of Crystallography, 2010) Peulecke, N.; Peitz, S.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.
    The title compound, [Cr(C26H26P2Si)(CO) 4], was obtained by the reaction of Ph2PSiMe 2PPh2 with Cr(CO)6 in refluxing toluene by ligand exchange. The CrC4P2 coordination geometry at the Cr atom is distorted octa-hedral, with a P - Cr - P bite angle of 80.27 (1)°.