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51.
The title compound [Bi(OSitBuPh2)3] ( 1 ) was prepared by the reaction of [Bi(OtBu)3] with tBuPh2SiOH in toluene at room temperature. The compound crystallizes in the monoclinic space group P21/n with the lattice constants a = 17.610(1), b = 20.153(1), c = 26.655(1) Å and β = 105.503(3)°. In the solid state a dimer is observed as a result of weak bismuth π‐arene interactions. The bismuth arene centroid distance amounts to 3.340(7) Å. Thermolysis of compound 1 performed under argon gave a heterogeneous product. The powder X‐ray diffraction analysis of the latter shows elementary bismuth as the only crystalline phase. 相似文献
52.
Max Hofmann Leonard Rößner Prof. Dr. Marc Armbrüster Prof. Dr. Michael Mehring 《ChemistryOpen》2020,9(3):277-284
Thin coatings of Bi2O3 were deposited on glass substrates by ultrasonic spray coating of THF solutions of the molecular precursor [Bi38O45(OMc)24(DMSO)9] ⋅ 2DMSO ⋅ 7H2O (OMc=O2CC3H5) followed by hydrolysis and subsequent annealing. Depending on the synthetic protocol, the bismuth oxido cluster was transformed into either α- or β-Bi2O3. The as-synthesized Bi2O3 coatings were characterized by powder X-ray diffraction (PXRD), thickness measurements, diffuse reflectance UV-Vis spectroscopy (DRS), photoluminescence (PL) spectroscopy, Raman spectroscopy and scanning electron microscopy (SEM). The thin coatings (thickness: 5–16 μm) were compared with regard to their performance in photocatalytic rhodamine B (RhB) decomposition under visible light irradiation. The β-Bi2O3 coatings, that showed the highest photocatalytic activity, were used for the photocatalytic decomposition of other pollutants such as triclosan and ethinyl estradiol. In addition, the interplay between the photooxidation that is induced by the excitation of the catalyst using visible light and the photosensitized decomposition pathway was studied by degradation experiments of aqueous rhodamine B solutions using β-Bi2O3 coatings. 相似文献
53.
The title compound is a polymorph of [Na11(OSiMe3)10(OH)] and was crystallized from a toluene solution containing NaOSiMe3 and water. The molecular structure is best described as being composed of two subunits, a square antiprism built from eight sodium atoms and an Na4O4 heterocubane, both sharing a sodium atom. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
54.
Electron spin—echo spectroscopy was applied to undoped cis/trans- and pure trans-polyacetylene. Three different types of defects, namely (1) a local defect (ld), (2) a distributed defect (dd) (trapped soliton) and (3) a highly mobile defect (md) (soliton) could be distinguished. The corresponding relaxation times T1, T2 are determined. 相似文献
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R. K. Kremer E. Sigmund V. Hizhnyakov F. Hentsch A. Simon K. A. Müller M. Mehring 《Zeitschrift für Physik B Condensed Matter》1992,86(3):319-324
We report on the formation of conducting phases in slightly doped La2CuO4 samples by the existence of a percolative phase separation. Phase separation can be quenched by rapid cooling and can be restored by the application of a 3 T magnetic field. Magnetically polarizable quasiparticles are shown to be formed by hole doping which fuse to form percolative conducting and below 37 K superconducting phases. 相似文献
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The reaction of the basic bismuth nitrate [Bi(6)O(4)(OH)(4)](NO(3))(6)·H(2)O with sodium methacrylate in DMSO gave [Bi(38)O(45)(OMc)(24)(DMSO)(9)]·2DMSO·7H(2)O (OMc = O(2)CC(3)H(5)), which is highly soluble in organic solvents. By copolymerization of the bismuth oxido cluster with methyl methacrylate transparent, radiopaque organic-inorganic hybrid materials were obtained. 相似文献
60.
M. Mehring 《Applied magnetic resonance》1992,3(3-4):383-421
An introduction to the models which are usually applied, when interpreting the NMR (nuclear magnetic resonance) parameter Knight shift (K s) and spin-lattice relaxation rate 1/T 1 in the normal and the superconducting state of high-temperature superconductors, is given. The different hyperfine interaction parameters involved, as well as the static and dynamic susceptibility χ(q,ω) will be discussed. I will point at those highlights as antiferromagnetic correlations, spin gap and vortex lattice dynamics which have emerged from the analysis of the NMR data. 相似文献