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The interaction of atomic oxygen with the clean Cu(100) surface has been studied by means of cluster and periodic slab models density functional theory in the present paper. The Cu(4,9,4) cluster and a three-layer slab with c(2×2) structure are used to model the perfect Cu(100) surface. Three possible adsorption sites,top, bridge and hollow site, were considered in the calculations. The predicted results show that the hollow site is the prefer site for atomic oxygen adsorbed on Cu(100) surface energetically. This is in good agreement with the experiment. The calculated binding energies are respective 2.014, 3.154 and 3.942 eV for top, bridge and hollow sites at mPW1PW91/LanL2dz level for the cluster model. The geometry of Cu(100) surface has also been optimized theoretically with various density functional methods and the results show that the prediction from the B3PW91/LanL2dz and mPW1PW91/LanL2dz reproduce the experimental observation.The frontier molecular orbitals and partial density of states analysis show that the electron transfer from the d orbital of substrate to the p orbital of the surface oxygen atom. 相似文献
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[2+2]型Schiff碱大环化合物及其配合物的合成 总被引:1,自引:0,他引:1
利用Mn2 ,Ba2 作为模板离子,合成了一类新型的Schiff碱型大环化合物,Mn2 用于L1和L2的合成,并在洗涤时自动解络,L3和L4的合成以Ba2 为模板.L3和L4的Ba2 配合物经与Na2SO水溶液反应解络,得到自由配体L3和L4.上述大环配体和各种配合物均经元素分析,IR,1H NMR,MS等证实了它们的结构和组成. 相似文献
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利用Mn^2+,Ba^2+及Sr^2+作为模板离子,合成了一类新型的含呋喃环系 Schiff碱型大环化合物,如L^1和配合物L^2Ba(ClO4)2,L^3Ba(ClO4)2和L^4Ba (ClO4)2.L^2-L^4的Ba^2+配合物经与NaSO4水溶液反应解络,得到自由配体L^2, L^3和L^4,配体L^2和L^3分别与Sr^2+作用,得到配合物L^2Sr(ClO4)2和L^3Sr (ClO4)2。上述大环配体和各种配合物均经元素分析,IR,^1H NMR,MS等证实了它 们的结构和组成。 相似文献
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采用密度泛函理论探讨了 2-氯噻吩分子在 Rh(111) 表面上吸附行为. 结果表明, 平行的 hol 位及 bridge 位上的吸附最稳定. 吸附后, 2-氯噻吩键长发生明显变化, 分子平面被扭曲, 分子中 C–H(Cl, S) 相对于金属表面倾斜上翘. 垂直吸附模式不如平行吸附模式稳定, 但吸附后噻吩环未发生变形. hol 及 bridge 吸附模式下 2-氯噻吩的芳香性已遭破坏, 噻吩环上的碳原子呈现准 sp3 杂化. 在平行的 hol 位吸附后, 2-氯噻吩环累计得到 0.77 个电子, 而 Rh(111) 表面累计失去 1.19 个电子. 相似文献
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合成了1,5-二(2-氨基(或硝基)苯氧基)-N-苯基-3-氮杂戊烷。对它们的结构作了元素分析、红外光谱、核磁共振谱及质谱鉴定。 相似文献
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Thiophene adsorption on the Rh(111) surfaces has been investigated by density functional theory.The results show that the adsorption at the hollow and bridge sites is the most stable.The molecular plane of the thiophene ring is distorted,the C=C bond is stretched to 1.448 and the C-C bond is shortened to 1.390.The C-H bonds tilt 22~42oaway from the surface.The calculated adsorption geometries are in reasonable agreement with population analysis and density of states.The thiophene molecule obtains 0.74 electrons,reflecting the interaction between the lone pair of sulfur and the d-orbitals of metal.The reaction paths and transition states for desulfurization of the molecule have been investigated.The bridge adsorption structure of thiophene leads to a thiol via an activated reaction with an energetic barrier of 0.30 eV.This second step is slightly difficult,and dissociation into a C4H4 fragment and a sulfur atom is possible,with an energetic barrier of 0.40 eV. 相似文献
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Thiophene adsorption on the(111) surfaces of Pd and Pt have been investigated by density functional theory.The results indicate that the adsorption at the hollow sites is the most stable.To our interest,the molecular plane of thiophene ring is distorted with C=C bond being elongated to 1.450 and C-C bond being shortened to 1.347 ,and the C-H bonds tilt 13.91~44.05o away from this plane.Furthermore,analysis on population and density of states verified the calculated adsorption geometries.Finally,charge analysis suggests that thiophene molecule is an electron acceptor,reflecting the interaction between the lone pair of sulfur and the d-orbitals of metal. 相似文献
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以2,6-二溴甲基吡啶及2,5-二氯甲基噻吩分别与对甲基苯磺酰胺进行缩合反应得到新的大环化合物1,9,17,25-四对甲基苯磺酰基大环多胺{[32]-Py4N4Ts4}与1,8,15,22-四对甲基苯磺酰基大环化合物{[28]-Th4N4Ts4}。其中[32]-Py4N4Ts4在浓硫酸中脱去四个对甲基苯磺酰基后又得到新的大环多胺化合物[32]-Py4N4H4,并由紫外吸收光谱测定出其与Cu(Ⅱ)配合的配位比为1:2,证明形成了双核配合物。 相似文献