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11.
Chuan-Ming Jin Guo-Yuan Lu Yan Xu Qian Li Fang Liu Xiao-Zeng You 《Journal of chemical crystallography》2001,31(6):301-305
The crystal structure of 25,27-bis[(2-cyanophenyl)methoxy] calix[4]arene (C44H34N2O4) was determined by X-ray crystallographic analysis. It possesses space group R
, with a = b = 35.993(8) Å, c = 13.842(3) Å, = = 90°, = 120°, and D
calc = 1.260 mg/cm3 for Z = 18. Crystal data indicate that Compound 1 exists in a pinched-cone conformation with intramolecular hydrogen bonds. 相似文献
12.
The dynamical entanglement for Fermi coupled C--H stretch and bend
vibrations in molecule CHD3 is studied in terms of two
negativities and the reduced von Neumann entropy, where initial
states are taken to be direct products of photon-added coherent
states on each mode. It is demonstrated that the negativity defined
by the sum of negative eigenvalues of the partial transpose of
density matrices is positively correlated with the von Neumann
entropy. The entanglement difference between photon-added coherent
states and usual coherent states is discussed as well. 相似文献
13.
A zinc(Ⅱ) coordination polymer [Zn2(2-mBIM)2(SUC)2]n (1, 2-mBIM = bis(2-methylimidazo-1-yl) methane, SUC = succinate anion) has been synthesized and characterized by X-ray diffraction. Complex 1 crystallizes in the triclinic space group P1 with a = 9.4871(8), b = 12.9789(5), c = 14.0230(5), α = 90.474(1), β = 90.3560(10), γ = 109.691(1)°, V = 1529.94(15)3 , Z = 2, Dc = 1.553 mg/m3 , μ = 1.63 mm-1 , F(000) = 736, the final R = 0.0645 and wR = 0.0951 for 4067 observed reflections with I > 2σ(I). Each Zn atom was coordinated by two individual 2-mBIM ligands in a cis-conformation and two monodentate coordinated succinate anions in a gauche conformation, resulting in the formation of a two-dimensional supramolecular network containing a cationic 16-membered macrometallacycle and a 28-membered macrometallacycle. The result also indicates that the conformation of the ligands has a strong influence on the structure of the supramolecular network. 相似文献
14.
A novel method for the preparation of chromogenic calixarenes with azo groups was reported.p-Substituted(-NO2,-CH3,-Cl)amilines were diazotized with isoamyl nitrite in EtONa/EtOH under refluxing condition.Fifteen mono-,bis-,tris-and tetrakis(p-substituted phenyl)azo calix[4]arenes (including proximal and distal isomers) were obtainged respectively by diazo-coupling in different molar ratio to calix[4]arenes(1) under pH=7.5-9.0 in non-aqueous solution at 0-5℃.^1H NMR and ^13C NMR spectra of (p-substtituted phenyl)azo calix[4]-arenes indicated that they existed in cone conformation in solution. 相似文献
15.
A series of both imidazolium- and triazolium-based unsymmetric dicationic salts with alkyl and polyfluoroalkyl substituents were prepared and characterized. Most of them can be classified as ionic liquids (MP < 100 degrees C). Key physical properties, such as melting point, thermal stability, density, and solubility in common solvents were determined and were compared with those of the related monocationic imidazolium- or triazolium-based salts. The effects of anions and substituents bonded to the triazolium and imidazolium cations on these properties were examined. 1-(3-Butyl-imidazolium-1-yl)methylene-(4-butyl-1,2,4-triazolium diiodide) (2d), the precursor of 1-(3-butylimidazolium-1-yl)methylene-(4-butyl-1,2,4-triazolium) bi[bis(trifluoromethanesulfonyl)amide] (3d), reacted with Pd(OAc)(2) at 120 degrees C to generate a binuclear palladium(II) dicarbene complex. The palladium(II) complex was characterized by single-crystal X-ray diffraction analysis and was used as a catalyst precursor for palladium-catalyzed Heck cross-coupling reactions in 3d. Preliminary results show that 3d could serve as both the solvent and catalyst support in the catalytic reactions. 相似文献
16.
Composition dependence of quaternary CuIn1-x GaxSe2 films on Ga content has been systematically investigated by Raman scattering. The dominant A1 mode shifts from 174cm^-1 for CuInSe2 to 185cm^-1 for CuGaSe2 in an approximately polynomial curve other than a linear curve, indicating existence of asymmetric distribution of Ga and In on a microscopic scale in films. With Ga content x 〉 0.3, the significantly broadening and intensity decrease of A1 modes suggest the degradation of crystalline quality of chalcopyrite phase. Additionally, the quenching of additional Raman band at 183cm^-1 for the Ga-rich films reveals that CuAu-ordered phase can coexist in nominal chalcopyrite CuInSe2 films but not in CuGaSe2, due to Ga inhibition effect. 相似文献
17.
Simulation of the relativistic backward wave oscillator with a sinusoidal guiding magnetic field 总被引:1,自引:1,他引:1
A simulation is carried out to investigate a relativistic backward wave oscillator (RBWO) with a sinusoidal guiding magnetic field. In the numerical simulation, a microwave output power of 1.33 GW at 9.57 GHz microwave frequency with 33% conversion efficiency is achieved. It is a significant attempt which is helpful for developing a practical high power microwave (HPM) source guided by a permanent magnetic field. 相似文献
18.
以不同的多极量子数和初态,我们用约化的线性熵研究CH(CH3)3 的耦合CH伸缩和弯曲振动的动力学纠缠,结果表明:在多极量子数大于等于3时,态|0,2N>的最大纠缠能在较短的时间内得到;态|N,0>的纠缠振荡频率比态|0,2N>的要小,而振荡的幅度要大. 相似文献
19.
The effect of composition on structural and electronic properties in polycrystalline CuGaSe2 thin film 下载免费PDF全文
Polycrystalline CuGaSe2 thin films on Mo-coated soda-lime glass substrates have been synthesized by coevaporation process from Cu, Ga and Se sources. Structural and electrical properties of the as-grown CuGaSe2 films strongly depend on the film composition. Stoichiometric CuGaSe2 is fabricated, as indicated by x-ray diffraction spectroscope (XRD) and x-ray fluorescence (XRF). A two-phase region is composed of CuGaSe2 and Cu2-xSe phases for Cu-rich films, and CuGaSe2 and CuGa3Se5 phases for Ga-rich films, respectively. Morphological properties are detected by scanning electron microscope (SEM) for various compositional films, the grain sizes of the CuGaSe2films decrease with the extent of deviation from stoichiometric composition. Raman spectroscopy of Cu-rich samples shows that there exist large Cu-Se particles on the film surface. The results from Hall effect measurements for typical samples indicate that CuGaSe2 films are always of p-type semiconductor from Cu-rich to Ga-rich. Stoichiometric CuGaSe2 films exhibit relatively large mobility than any other compositional films. Finally, polycrystalline CuGaSe2 thin film solar cell with a best conversion efficiency of 6.02% has been achieved under the standard air mass (AM)1.5 spectrum for 100mW/cm^2 at room temperature (aperture area, 0.24cm^2). The open circuit voltage of the CuGaSe2 solar cells is close to770 mV. 相似文献
20.
SHI Zheng-Wei JIN Chuan-Ming LU Guo-Yuan 《有机化学》2003,23(Z1):161-161
Calixcrowns carrying bridging polyethyleneoxy moieties on the lower rim, which combine calixarene and crown ether in a single molecule, are a novel class of host compounds which have attracted increasing attention because of their increased ability for selective complexation of cations and neutral molecules compared with crown ethers or cal ixarenes. 相似文献