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Synthesis, crystal structure, and dielectric properties of [C6H4(NH3)2]2ClBiCl6.H2O are reported. The compound crystallizes in the monoclinic system with space group P21/n. The unit cell dimensions are a = 9.836(5), b = 19.582(5), c = 13.082(5) ?, β = 104.731(5)° with Z = 4. The atomic arrangement can be described by an alternation of organic and inorganic layers. The anionic layer is built
up of octahedral of [BiCl6]3- arranged in sandwich between the organic layers. The crystal packing is governed by means of the ionic N–H···Cl hydrogen
bonds, forming a three-dimensional network. The dielectric properties have been investigated at temperature range from 297
to 410 K at various frequencies (10 Hz–100 kHz). Dielectric studies were performed to confirm results obtained with thermal
analysis. The evolution of dielectric constant as a function of temperature and frequency of single crystal has been investigated
in order to determine some related parameters. 相似文献
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Houcine ZoghlamiMoufida Romdhani-Younes Mohamed Moncef Chaabouni Ahmed Baklouti 《Tetrahedron letters》2011,52(8):881-883
The solvent-free reaction of oligoethylene glycol diglycidyl ethers with dimercaptoethane in the presence of benzyltrimethylammonium hydroxide (Triton B) gave, via regiospecific epoxide opening reactions, dihydroxy dithiacrown ethers in excellent yields and in short reaction times. 相似文献
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Chehrouri M Fillion JH Chaabouni H Mokrane H Congiu E Dulieu F Matar E Michaut X Lemaire JL 《Physical chemistry chemical physics : PCCP》2011,13(6):2172-2178
Nuclear spin conversion (NSC) of ortho- to para-H(2) and para- to ortho-D(2) has been investigated on an amorphous solid water (ASW) surface at 10 K, in the presence of co-adsorbed O(2). The dynamics of the nuclear spin conversion could be revealed by combination of resonance enhanced multiphoton ionization spectroscopy (REMPI) with temperature programmed desorption (TPD) experiments. The conversion rates are consistent with a diffusion of molecular hydrogen inducing a nuclear spin conversion enhanced in the vicinity of molecular oxygen. The conversion times were found to increase with decreasing O(2) and H(2) coverage. Finally, on oxygen free ASW surface, the extremely long conversion characteristic times measured showed that such surface is not an efficient catalyst for NSC, in contradiction with hypothesis commonly made for interstellar medium. 相似文献
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Penthylene diammonium pentachlorothallate(III) exhibits a phase transition at 316 K <artwork name="GPHT21157eu1"> This transition has been characterized by optical birefringence, dielectric measurements differential scanning calorimetry and spectroscopic measurements on polycrystalline samples. The space group and the cell parameters of phase I were determined by X-ray diffraction from single crystals. Phase I has space group P212121, with Z = 4, a = 7.696(3), b = 13.2890(17) and c = 13.503(18) Å. The transition is both displacive and order-disorder involving mainly conformational changes of the organic chain [NH3(CH2)5NH3]2+ coupled with distortion of the TlCl6 octahedra. This behaviour and the crystal dynamics will be discussed and compared with those found in the literature for homologous compounds. 相似文献
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A convenient method for the one-pot conversion of olefins into the corresponding enol thioethers is reported. The products were obtained via the N-bromosuccinimide cobromination reaction of olefins with thiols in basic medium. Steric hindrance present in the product alkenes may explain the stereochemistry observed. 相似文献
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Four new fulgimides possessing a fluorescent coumarin unit were synthesized from the corresponding fulgides, and their photochromic as well as fluorescence properties were investigated. The open-ring forms of coumarin fulgimides were found to exhibit fluorescence in the visible region. Upon exposure to UV light, the fulgimides were transformed into the nonfluorescent closed-ring forms, which can be reverted to the initial fluorescent open-ring forms on exposure to visible light. The efficiency of quenching of fluorescence was as high as 95% at the photostationary state of UV irradiation. 相似文献