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Martina Dotzler Astrid Schmidt Jochen Ellermann Falk A. Knoch Matthias Moll Walter Bauer 《Polyhedron》1996,15(24):4425-4433
BiBr3 or SbI3 react at 20°C with LiN(PPh2)2 (1) to give elementary Bi or Sb and the P---P coupled phosphazene ligand Ph2P---N=PPh2---PPh2=N---PPh2 (2). The reaction of AsI3 with 1 at room temperature formed yellow needles of the eight-membered heterocycle
(3), whereas AsI3 interacted at 80°C with 1 in the molar ratio of 1:3 to give elementary arsenic and 2. Treatment of AsI3 and 1 at 20°C in a 1:2 stoichiometry yielded the seven-membered, cyclic arsenium(I) salt I·4THF (5·4THF), which was characterized by elemental analysis, conductivity, mass, IR and NMR spectroscopy and single-crystal X-ray structural analysis. 相似文献
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Walter Bauer Jochen Ellermann Martina Dotzler Diana Pohl Frank W. Heinemann Matthias Moll 《无机化学与普通化学杂志》2000,626(2):574-587
Chemistry of Polyfunctional Molecules. 133. X‐Ray Crystal Structural, Solid‐state 31P CP/MAS NMR, TOSS, 31P COSY NMR, and Mechanistic Contributions to the Co‐ordination Chemistry of Octacarbonyldicobalt with the Ligands Bis(diphenylphosphanyl)amine, Bis(diphenylphosphanyl)methane, and 1,1,1‐Tris(diphenylphosphanyl)ethane Co2(CO)8 reacts with bis(diphenylphosphanyl)amine, HN(PPh2)2 (Hdppa, 1 ), in two steps to afford the known compound [Co(CO)(Hdppa‐κ2P)2][Co(CO)4] · 2 THF ( 6 a · 2 THF). The intermediate [Co(CO)2(Hdppa‐κ2P) · (Hdppa‐κP)][Co(CO)4] · dioxane · n‐pentane ( 5 · dioxane · n‐pentane) was isolated for the first time and was characterized by X‐ray analysis. The cation 5 + exhibits a slightly distorted trigonal‐bipyramidal geometry. Detailed 31P‐NMR investigations (solid‐state CP/MAS NMR, TOSS, 31P‐COSY, 31P‐EXSY) showed that the additional tautomer [Co(CO)2(Hdppa‐κ2P)(Ph2P–N=P(H)Ph2‐κP)]+ ( 5 ′+) is present in solution. The tautomer equilibrium is slow in the NMR time scale. In contrast to the solid state only tetragonal pyramidal species of 5 are found in solution. At –90 °C there is slow exchange between the three diastereomeric species 5 a +– 5 c +. Compound 5 forms [Co(CO) · (Hdppa‐κ2P)2]BPh4 · THF ( 6 b · THF) in THF with NaBPh4 under CO‐Elimination. A X‐ray diffraction investigation shows that the cation 6 + consists of a slightly distorted trigonal‐bipyramidal co‐ordination polyeder. However, a distorted tetragonal‐pyramidal structure has been found for the cation 7 + of the related compound [Co(CO)(dppm)2][Co(CO)4] · 2 THF ( 7 · 2 THF; dppm = bis(diphenylphosphanyl)methane, Ph2PCH2PPh2). A comparison with the known [8] trigonal‐bipyramidal stereoisomer, ascertained for 7 + of the solvent‐free 7 , is described. In solutions of 6 a · 2 THF and 7 · 2 THF 13C{1H}‐ and 31P{1H}‐NMR spectra indicate an exchange of all CO and organophosphane molecules between cobalt(I) cation and cobalt(–I) anion. A concerted mechanism for the exchange process is discussed. CO elimination leads to discontinuance of the cyclic mechanism by forming binuclear substitution products such as the isolated Co2(CO)2 · (μ‐CO)2(μ‐dppm)2 · 0.83 THF ( 8 · 0.83 THF), which was characterized by spectroscopy and X‐ray analysis. For the dissolved [Co(CO)2CH3C(CH2PPh2)3][Co(CO)4] · 0.83 n‐pentane ( 9 a · 0.83 n‐pentane) no CO and triphos exchange processes between the cation and the anion are observed. Metathesis of 9 a · 0.83 n‐pentane with NaBPh4 yields [Co(CO)2CH3C(CH2PPh2)3]BPh4 ( 9 b ) which has been characterized by single‐crystal X‐ray analysis. The cation shows a small distorted tetragonal‐pyramidal structure. 相似文献
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The technique of ferromagnetic resonance at 23 GHz has been used to determine the first three anisotropy constants of pure Ni down to 4.2K. A temperature and orientation dependent linewidth has also been observed. 相似文献
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AC Cruickshank CJ Dotzler S Din S Heutz MF Toney MP Ryan 《Journal of the American Chemical Society》2012,134(35):14302-14305
The structure of copper phthalocyanine (CuPc) thin films (5-100 nm) deposited on single-crystal ZnO(11?00) substrates by organic molecular beam deposition was determined from grazing-incidence X-ray diffraction reciprocal space maps. The crystal structure was identified as the metastable polymorph α-CuPc, but the molecular stacking was found to vary depending on the film thickness: for thin films, a herringbone arrangement was observed, whereas for films thicker than 10 nm, coexistence of both the herringbone and brickstone arrangements was found. We propose a modified structure for the herringbone phase with a larger monoclinic β angle, which leads to intrastack Cu-Cu distances closer to those in the brickstone phase. This structural basis enables an understanding of the functional properties (e.g., light absorption and charge transport) of (opto)electronic devices fabricated from CuPc/ZnO hybrid systems. 相似文献
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LaGrow AP Ingham B Cheong S Williams GV Dotzler C Toney MF Jefferson DA Corbos EC Bishop PT Cookson J Tilley RD 《Journal of the American Chemical Society》2012,134(2):855-858
This Communication describes the synthesis of highly monodispersed 12 nm nickel nanocubes. The cubic shape was achieved by using trioctylphosphine and hexadecylamine surfactants under a reducing hydrogen atmosphere to favor thermodynamic growth and the stabilization of {100} facets. Varying the metal precursor to trioctylphosphine ratio was found to alter the nanoparticle size and shape from 5 nm spherical nanoparticles to 12 nm nanocubes. High-resolution transmission electron microscopy showed that the nanocubes are protected from further oxidation by a 1 nm NiO shell. Synchrotron-based X-ray diffraction techniques showed the nickel nanocubes order into [100] aligned arrays. Magnetic studies showed the nickel nanocubes have over 4 times enhancement in magnetic saturation compared to spherical superparamagnetic nickel nanoparticles. 相似文献