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71.
Six fully optimized structures of the aza-calix[2]arene[2]-triazines/RDX supramo-lecular complexes have been obtained at the DFT-B3LYP/6-311++G** level,and the corresponding intermolecular interactions have been investigated using the B3LYP,mPWPW91 and MP2 methods at the 6-311++G** level,respectively.The natural bond orbital(NBO) and atoms in molecules(AIM) analyses have been performed to reveal the origin of interactions.To our interest,the result indicates that the strongest interaction is up to -22.34 kJ/mol after basis set superposition error(BSSE) and zero point energy(ZPE) correction at the MP2/6-311++G** level.Furthermore,the intermolecular interactions between aza-calix[2]arene[2]-triazines with the substituted amidos and RDX are stronger than those of other complexes.Thus,the complexes with amidos can be used as the candidates to increase the stability of explosive and eliminate the explosive wastewater.  相似文献   
72.
摘要所选体系为非路易斯分子,即分子中含有一个可分裂的C—C键,两个电子占据非键分子轨道,对这类分子的能量和稳定性的研究已有报道.根据体系中两个自由基电子相互作用不同,该类分子可能具有三种电子态.本文采用密度泛函和从头算等方法在不同基组水平上,对四氢吡咯双自由基(体系a)及其两个等电子体系的NLO性质进行了理论研究.采用不同方法和基组优化体系a三种电子态的几何结构,  相似文献   
73.
以Cu(Ⅱ)作为中心离子,5-氟脲嘧啶(5-Fu)和邻菲咯啉(Phen)作为配体,合成了[Cu(Phen)(5-Fu)2](NO3)2配合物;利用元素分析和红外光谱分析了配合物的组成和化学结构;利用荧光光谱考察了其与牛血清白蛋白(BSA)的相互作用.结果表明.配合物与BSA作用可导致BSA内源荧光猝灭;其猝灭机理为静态...  相似文献   
74.
采用同步荧光光谱技术研究了pH=7.40的Tris-HCl缓冲体系中水飞蓟素与牛血清白蛋白(BSA)的相互作用以及水飞蓟素对BSA构象的影响.结果表明,水飞蓟素对BSA的荧光猝灭过程为静态猝灭,结合热力学参数△rH∞=-45.21 kJ·mol-1,△rSm=-61.61 J·K-1·mol-1;据此可以推断,水飞蓟素...  相似文献   
75.
利用荧光光谱和吸收光谱研究了贝加因与牛血清白蛋白(BSA)的相互作用,由Van't Hoff方程计算了反应的热力学参数,并根据Stern-Volmer方程计算了不同温度下的结合位点和结合常数.结果表明,贝加因可静态猝灭BSA的内源荧光;二者相互作用的焓变和熵变均大于零,说明疏水作用力是二者之间的主要作用力.与此同时,贝...  相似文献   
76.
采用亲和毛细管电泳技术对粗提单胺氧化酶(MAO)与其专一性底物犬尿胺(Kyn)的相互作用进行研究,并引入MAO抑制剂氯吉兰对该特异性相互作用进行验证.结果表明,随着缓冲液中MAO浓度的增大,Kyn相对两个内标的迁移时间比率(RMTR)逐渐减小.而加入氯吉兰后,Kyn的RMTR值比未加入抑制剂时有所增大.说明MAO活性位...  相似文献   
77.
The reaction of N-tosylatirdine with 1,2-diaminopropane in dry benzene solution yields an intermediate H2L, N,N,N',N'-tetrakis(2-(p-tolylsulfonyl)aminoethyl) propane-1,2-diamine. The mononuclear copper(Ⅱ) complex, [CuLH2O]·H2O, was synthesized by the reaction between the intermediate and copper(Ⅱ) in absolute methanol. The complex has been characterized by IR, UV-vis and X-ray diffraction technology, and its crystal crystallizes in the orthorhombic system, space group Pbca with a = 15.589(1), b = 21.897(2), c = 27.645(2) , V = 9436.4(1) 3, Dc = 1.352 g/cm3, Z = 8, Mr = 960.68, F(000) = 4040, μ(MoKa) = 0.698 mm-1, S = 0.98, R = 0.0537 and wR = 0.1180 for 5804 observed reflections (I > 2σ(I)). In the crystal structure, a one-dimensional chain is formed by abundant hydrogen bond interactions. The interaction of the complex with DNA was monitored using agarose gel electrophoresis. The result shows that the complex can transform the supercoiled to nicked and liner forms, and has a concentration-dependent cleavage activity.  相似文献   
78.
The reaction of CdCl2 with 6,7-dicyanodipyridoquinoxaline (DICNQ) by solvothermal reaction gives rise to a coordination polymer [CdCl2(DICNQ)]n 1. Single-crystal X-ray diffraction analysis reveals that the compound in space group Pbcn creates 1-D chloro-bridging chains. Crystal data for 1: a = 6.756(1), b = 35.371(6), c = 7.027(1) , V = 1679.1(5) 3, Z = 4.00, C16H6CdCl2N6, Mr = 465.57, Dc = 1.842 g/cm3, μ = 1.630 mm-1, F(000) = 904, S = 1.005 and T = 293(2) K. The final R = 0.0376 and wR = 0.1029 for 1291 observed reflections with I > 2σ(I), and R = 0.0499 and wR = 0.1125 for all data. The 1-D chloro-bridging chains are parallel-stacked in the a and b directions, and further stabilized through π-stacking interactions, hydrogen-bonding interactions and C≡N···π interactions to generate a 3-D structure. Compound 1 displays intense bluish-green photoluminescence from the intraligand charge-transfer of the DICNQ ligand and the Cl--to-DICNQ charge-transfer mechanism which is probed by the density of states (DOS) calculations.  相似文献   
79.
韦昊  吴刚  刘振锋 《结构化学》2011,30(9):1257-1264
Two complexes, [Cu2(Htdb)4(H2O)2] (1) and [Cd(bipy)2(Hmcmbc)2] (2) (H2tdb = 2,2-thiodibenzoic acid, H2mcmbc = m-(carboxyl-methyloxy)-benzenecarboxylic acid, bipy = 4,4'-bipyridine), have been prepared, and were characterized by elemental analysis, FT-IR and single-crystal X-ray diffraction. Structures indicate that complex 1 is a single molecule, and 2 is a one-dimensional chain. Their two-and three-dimensional frameworks are constructed through hydrogen bonding, π…π or C–H…π stacking, and such other weak interactions. The cyclic voltametric behavior of complex 1 and luminescence property of complex 2 were investigated. 1 belongs to the triclinic system, space group P with a = 7.8607(6), b = 11.7619(9), c = 15.3481(12) , α = 109.3670(10), β = 92.4420(10), γ = 92.0450(10)°, V = 1335.65(18) 3, Mr = 1256.26, Dc = 1.5619(2) g/cm3, F(000) = 642, μ = 1.029 mm–1, Z = 1, the final R = 0.0289 and wR = 0.0763 for 5199 observed reflections with I > 2σ(I). Complex 2 crystallizes in triclinic, space group P with a = 9.6378(10), b = 9.7508(10), c = 19.055(2) , α = 88.7020(10), β = 80.5260(10), γ = 69.2000(10)o, V = 1649.9(3) 3, Mr = 815.07, Dc = 1.641 g/cm3, μ = 0.732 mm-1, F(000) = 828, Z = 2, the final R = 0.0511 and wR = 0.1149 for 4729 observed reflections (I > 2σ(I)).  相似文献   
80.
王崇臣  王鹏 《结构化学》2011,30(6):811-818
The title complexes(NH4)[Ag(dpe)(H2bptc)](1) and Ag2(bpy)(ox)·7H2O(2) were synthesized via slow evaporation at room temperature,and characterized by elemental analysis and infrared spectra.The crystal of 1 crystallizes in triclinic,space group P1 with a = 8.3959(7),b = 11.8088(12),c = 12.8175(13) ,α = 85.507(2),β = 79.245(1),γ = 84.174(2)o,V = 1239.7(2) 3,Z = 2,C28H22AgN3O8,Mr = 636.36,Dc = 1.705 g/cm3,F(000) = 644 and μ(MoKα) = 0.874 mm-1.The final R = 0.0479 and wR = 0.1426 for 3632 observed reflections with I > 2σ(I) and R = 0.0559 and wR = 0.1503 for all data.The crystal of 2 crystallizes in orthorhombic,space group Pnna with a = 17.2291(17),b = 7.5289(6),c = 21.369(2),V = 2771.9(4) 3,Z = 4,C22H30Ag2N4O11,Mr = 742.24,Dc = 1.779 g/cm3,F(000) = 1488 and μ(MoKα) = 1.476 mm-1.The final R = 0.0648 and wR = 0.2058 for 1996 observed reflections with I > 2σ(I) and R = 0.0769 and wR = 0.2192 for all data.X-ray diffraction reveals that in complexes 1 and 2,both 1,2-di(4-pyridyl)ethylene and 4,4'-bipyridine act as typical bidentate N-donor ligands to link two Ag centers.3,3'4,4'-Biphenyltetracarboxylate and oxalate anions play the role of organic linkers and counter-ions to balance the cationic charge of AgI.The rich hydrogen-bonding interactions and ligand-unsupported Ag…Ag interactions as well as π-π stacking interactions contribute to the construction of three-dimensional sandwich-like frameworks.  相似文献   
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