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1.
用INDO系列方法对由(C59N)2和苯甲醚合成的衍生物C59(C6H4OCH3)N进行了理论研究,得到了分子的稳定构型.结果表明,C59(C6H4OCH3)N具有Cs对称性.以优化构型为基础讨论了分子的UV-Vis光谱、NMR谱线数,结果与实验符合得很好.本文还计算了C59(C6H4OCH3)N的二阶非线性光学系数βμ,结果表明这种物质具有较大的二阶非线性光学系数.  相似文献   

2.
合成了4个新型NiBDT配位化合物,BDT为具有9个S原子的杂戊烯.元素分析、IR谱、UV谱确定这4个新配合物的化学式分别为[(CH3)4N]2[Ni(C5S9)2](1),[(C2H5)4N]2·[Ni(C5S9)2](2),[(C4H9)4N]2[Ni(C5S9)2](3),[(C6H5)(CH3)3N]2[Ni(C5S9)2](4).采用Ito法对配合物1的X射线粉末图进行了指标化,确定该晶体属单斜晶系,简单晶格,晶胞参数:a=0.680nm,b=0.714nm,c=2.302nm,γ=111.4°,Z=2.  相似文献   

3.
用INDO系列方法对自由基C69N(Cs)及双体(C69N)2(C2h)进行了理论研究,结果表明:笼骨架上N的掺入使C70笼发生畸变,N向笼外突出,与氮相连的碳(6-6环上的C)自旋密度较大,2个C69N自由基在这个碳上以C-C单键连接,形成双体为C2h对称性,N与附近的3个碳均以单键连接,并不断开。理论计算的电子光谱与实验吻合较好,(C69N)2易分解为单体C69N.  相似文献   

4.
C59O的结构、电子光谱及NMR谱的理论预测   总被引:2,自引:0,他引:2  
用INDO系列方法对C60的取代产物C59O进行几何构型优化,得到Cs对称性的稳定构型,以此构型为基础,计算并预测了C59O的电子光谱和NMR谱.最后与C59O的等电子分子体C602-及C60O进行了比较.  相似文献   

5.
含有金刚烷胺的多金属氧酸盐的合成和抗流感病毒活性   总被引:9,自引:0,他引:9  
刘术侠  王春玲  于淼  李玉新  王恩波 《化学学报》2005,63(12):1069-1074
以金刚烷胺和1∶10 (Ln∶W), 1∶13(Ni或Mn∶V)系列多金属氧酸盐为原料, 合成了化学式分别为K4(C10H18N)5CeW10O36•2H2O (APOM-5), K4(C10H18N)5PrW10O36•2H2O (APOM-6), K3(C10H18N)4NiV13O38•H2O (APOM-12)和K3(C10H18N)4MnV13O38•H2O (APOM-13)的四种新的多金属氧酸盐, 并通过元素分析、IR光谱及1H NMR谱对其结构进行了表征. 在狗肾(Madin-Darby canine kidney, MDCK)细胞内, 对合成化合物进行了抗流感病毒A和B的活性研究. 发现APOM-13对流感病毒A, B两型均有明显的抑制活性, 而APOM-12只在浓度较高时对流感病毒A, B两型有抑制活性, 低浓度时, 活性不明显. APOM-5,6对A型流感病毒有效, 但对B型流感病毒抑制活性不明显. 另外发现APOM-12和APOM-13对流感病毒感染MDCK细胞病变效应(CPE)具有明显抑制作用, 且浓度越大抑制作用愈明显.  相似文献   

6.
1.制备一些新型的硫代膦酰氯,其中R'为C6H5,R"为C2H5O,C2H5,(CH3)2N,(C2H5)2N,C2H5S等。  相似文献   

7.
氮掺杂富勒烯(C59N)催化剂在氢燃料电池的氧还原反应中表现出良好的活性.然而,C59N上发生的氧还原反应路径的中间体和催化活性位点尚未被直接表征,阻碍了对C59N催化剂在氧还原反应中活性增强机制的理解.本文通过在模拟计算中考虑空间限制等离子体的不均匀分布,从理论上提出高空间分辨针尖增强拉曼散射可以有效地识别C59N上氧还原反应的不同中间体构型.通过调整聚焦的空间限制等离子体位置,氧还原反应中与O2-C59N相互作用有关联的振动模式可以被高空间分辨针尖增强拉曼散射光谱直接选择出来,并且得到增强.此外,选择出来的振动模式对应的高空间分辨针尖增强拉曼散射图像在吸附位点周围给出了拉曼热点,提供了氧还原反应在C59N上催化活性位点的原位观测细节.这些发现为今后通过高分辨率高空间分辨针尖增强拉曼散射技术在分子尺度上探索催化系统提供了良好的参考.  相似文献   

8.
朱任宏  方聖鼎 《化学学报》1965,31(3):222-228
从云南省昭通县产的雪上一枝蒿中共分得生物碱五种,其中三种为已知物,即烏头碱、次岛头碱和一枝蒿乙素,另二种为新生物碱,暂名为一枝蒿戊素和己素。一枝蒿戊素的分子式为C24H39O6N,其示性式为C19H22(OH)3(OCH3)3-(N·C2H5);一枝蒿己素的分子式为C24H39O7N,其示性式为C19H21(OH)4(OCH3)3(N·C2H5);另从云南省东川县出产的雪上一枝蒿中,尚分得一新生物碱,暂称为一枝蒿庚素,分子式为C21H31O3N,其示性式为C19H24(:O)(OH)2(N·C2H5)。  相似文献   

9.
用INDO/2和INDO/SCI方法计算了C60(C≡N)2和C60C(C≡N)2基态电子结构和电子光谱,所得结果与实验值基本一致.在此基础上,用ZINDO-SOS方法计算了两个分子的二阶非线性光学系数βijk和βμ,并对其结果进行了分析和讨论.结果表明,乙氰基与C60相连的两种碳笼衍生物都有大的非线性光学系数,C60C(C≡N)2是有希望的非线性光学材料.  相似文献   

10.
以氯化钴、 对叔丁基磺酰杯[4]芳烃(H4TC4A-SO2)和非对称性3-(1H-四唑-5-基)苯甲酸(H2L)为原料, 通过溶剂热法合成了一个具有四面体配位笼结构的16核化合物[Co16(TC4A-SO2)4(OH)4(L)8]·[(C8H20N)(C4H12N)2(C2H8N)]·solvent(Co16-TC4A-SO2). 采用X射线单晶衍射、 X射线粉末衍射、 热重分析、 红外光谱方法对配合物进行了表征. 将Co16-TC4A-SO2笼簇直接负载到碳纸上(Co16-TC4A-SO2/CP)用作工作电极, 其对析氧反应(OER)展现出较好的催化性能. 在1 mol/L KOH中, Co16-TC4A-SO2/CP在343.8 mV的过电位下达到10.0 mA/cm 2电流密度, Tafel斜率为79.31 mV/dec, 并且在20.0 mA/cm 2电流密度下表现出长达48 h的催化稳定性.  相似文献   

11.
在ZINDO方法基础上, 按完全态求和(SOS)公式, 编制了计算分子二阶非线性光学系数βijk的程序。研究了各种取代基在吩噻嗪的氮上取代后衍生物的结构和二阶非线性光学系数。结论是N上取代推电子基对增大二阶光学非线性有利, N上取代吸电子基对增大二阶光学非线性不利。扩大共轭范围对增大二阶光学非线性有利。对上述结果在微观上给予了解释。  相似文献   

12.
A simplified three-level model for γ, the molecular third-order nonlinear optical susceptibility, is presented and discussed. The perturbation theory-based approach suggests that there are three primary avenues to optimizing molecular four-wave mixing susceptibilities and that with each of these is associated a particular class of molecular electronic structures. The three electronic structure classes consist of (1) conjugated donor–acceptor dipolar molecules with a large secondorder susceptibility, β; (2) even-member conjugated chains such as -enes, -ynes, and ene–ynes with large two-photon dominated susceptibilities; and (3) “charged” odd-member conjugated chaines with large linear absorption dominated third-order susceptibilities such as squaryliums (perhaps, more generally, the polymethine dyes). Classes (1) and (2) have been known and investigated in the past, while recent results of ours suggest the existence of the third and perhaps final class.  相似文献   

13.
对一种碳笼骨架氮取代化合物C~5~9HN用INDO系列方法进行了理论研究,得到了C~5~9HN的电子结构、分子稳定性、UV-vis光谱及二阶非线性光学系数。  相似文献   

14.
Using the ab initio method, the geometrical structures of C(36) and the X (B,N)-doped isomers C(34)X(2) have been optimized. On the basis of the optimized structures, then, the third-order nonlinear optical polarizabilities gamma in the different optical processes of the third-harmonic generation, electric-field induced second-harmonic generation and degenerate four-wave mixing, and two-photon absorption (TPA) cross sections delta are calculated by using TDB3LYP method coupled with the sum-over-states method. The calculated results show that the one-photon allowed excitation process dominate the two-photon excitation process for C(36)-D(6h), whereas the two-photon allowed excitation process dominate the one-photon excitation process for C(36)-D(2d) and C(34)X(2) (B,N). It is found that the largest resonant TPA peaks of dopant fullerenes have a blueshift and the TPA cross sections have an enhancement compared with those of the parent fullerenes of isomers C(36)-D(6h) and C(36)-D(2d).  相似文献   

15.
用INDO/2和INDO/SCI方法,计算了C~6~0C(C=CH)~2基态电子结构和电子光谱,所得结果与实验结果基本一致.在此基础上,设计了C60(C=CH)~2,并用同样方法计算了电子结构和光谱.在正确的电子光谱基础上,用ZINDO-SOS方法计算了2个分子的二阶非线性光学系数β~i~j~k和β~μ,并对其结果进行了分析和讨论.结论是,乙炔基与C~6~0(C=CH)~2有更大的非线性光学系数,是有希望的非线性光学备选材料分子。  相似文献   

16.
在ZINDO方法基础上,按完全态求和(SOS)公式编制了计算分子二阶非线性光学系数βijk、βμ的程序,研究了各种吩噻嗪侧环取代衍生物的结构和二阶非线性光学性质,结论是侧环上推、拉电子取代基(不太弱)对增大二阶光学非线性都有利,扩大共轭范围也对增大二阶光学非线性有利,并对上述结果在微观上给予了解释。  相似文献   

17.
Low-energy excitations and optical absorption spectrum of C(60) are computed by using time-dependent (TD) Hartree-Fock, TD-density functional theory (TD-DFT), TD DFT-based tight-binding (TD-DFT-TB), and a semiempirical Zerner intermediate neglect of diatomic differential overlap method. A detailed comparison of experiment and theory for the excitation energies, optical gap, and absorption spectrum of C(60) is presented. It is found that electron correlations and correlation of excitations play important roles in accurately assigning the spectral features of C(60), and that the TD-DFT method with nonhybrid functionals or a local spin density approximation leads to more accurate excitation energies than with hybrid functionals. The level of agreement between theory and experiment for C(60) justifies similar calculations of the excitations and optical absorption spectrum of a monomeric azafullerene cation C(59)N(+), to serve as a spectroscopy reference for the characterization of carborane anion salts. Although it is an isoelectronic analogue to C(60), C(59)N(+) exhibits distinguishing spectral features different from C(60): (1) the first singlet is dipole-allowed and the optical gap is redshifted by 1.44 eV; (2) several weaker absorption maxima occur in the visible region; (3) the transient triplet-triplet absorption at 1.60 eV (775 nm) is much broader and the decay of the triplet state is much faster. The calculated spectra of C(59)N(+) characterize and explain well the measured ultraviolet-visible (UV-vis) and transient absorption spectra of the carborane anion salt [C(59)N][Ag(CB(11)H(6)Cl(6))(2)] [Kim et al., J. Am. Chem. Soc. 125, 4024 (2003)]. For the most stable isomer of C(48)N(12), we predict that the first singlet is dipole-allowed, the optical gap is redshifted by 1.22 eV relative to that of C(60), and optical absorption maxima occur at 585, 528, 443, 363, 340, 314, and 303 nm. We point out that the characterization of the UV-vis and transient absorption spectra of C(48)N(12) isomers is helpful in distinguishing the isomer structures required for applications in molecular electronics. For C(59)N(+) and C(48)N(12) as well as C(60), TD-DFT-TB yields reasonable agreement with TD-DFT calculations at a highly reduced cost. Our study suggests that C(60), C(59)N(+), and C(48)N(12), which differ in their optical gaps, have potential applications in polymer science, biology, and medicine as single-molecule fluorescent probes, in photovoltaics as the n-type emitter and/or p-type base of a p-n junction solar cell, and in nanoelectronics as fluorescence-based sensors and switches.  相似文献   

18.
用AM1和ZINDO方法研究了螺旋共轭化合物1',3',3'三甲基6羟基螺旋[2H-1-苯并吡喃2,2'-二氢吲哚](HBPS)及其光异构化产物的结构和光谱性质,从理论上研究了HBPS的光异构化反应过程,并在此基础上,用自编的完全态求和公式(SOS)程序计算了非线性光学系数.  相似文献   

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