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1.
严继民  叶学其 《化学学报》1995,53(9):833-836
本文用量化学及分子力学方法计算了(Na@C60)及(Cl@C60)中Na及Cl与C60之间的相互作用,总的相互作用是吸引。在静电相互作用、色散相互作用及电子云重排斥相互作用三项中前一项占90%以上,有着决定性的影响,色散相互作用约占5%。对电子云重叠排斥作用来说,由于Cl^-的半径比Na^+的大很多,所以在(Cl@C60)中这种作用要比在(Na@C60)中大很多。  相似文献   

2.
严安平  孙涛  王一波 《化学学报》2011,69(18):2075-2079
应用Perdew-Burke-Ernzerhof (PBE)密度泛函理论对5种可能存在的富勒烯与铈卟啉复合物进行了几何结构优化, 通过分子间距离及结合能数值, 确认了C60和铈卟啉可以通过非键相互作用形成超分子主-客体复合物, 且最有可能的作用位点为C60的C5:6键(相邻五元环与六元环共用碳-碳键). 应用扩展过渡态方法对结合能进行分解, 分解结果显示, 静电能对总吸引能的贡献约为60%, 说明静电作用是复合物稳定存在的最主要因素. 最后对复合物中的电子流向进行了研究, 结果表明复合物中电子的转移与主-客体间相互作用有一定联系, 且电子是从主体铈卟啉流向客体C60.  相似文献   

3.
重氮树脂型聚电解质复合物与SDS相互作用研究   总被引:2,自引:1,他引:1       下载免费PDF全文
由于聚电解质与表面活性剂的相互作用具有很多特别的性质而倍受关注[1~10],但具有感光性的重氮树脂作为正离子聚电解质与表面活性剂相互作用尚未见报道.本文研究了重氮树脂(DR)与聚苯乙烯磺酸钠(PSS)形成的聚电解复合物(DR-PSS)与十二烷基硫酸钠...  相似文献   

4.
聚合物基纳米复合物(PNCs)具有比传统高分子材料更加优异的光学、力学、热力学等性能,广泛应用于各个工程领域. 而纳米粒子(NPs)对材料性能提高的机理则是当前聚合物纳米复合物领域研究的重要问题,聚合物纳米复合体系相互作用的影响因素众多,至今尚未明确并完整建立复合体系相互作用与性能增强之间的关系. 本文总结了近年来关于纳米粒子填充聚合物基体力学性能的研究,从粒子-聚合物相互作用和粒子-粒子相互作用角度阐述了聚合物纳米复合体系力学性能的增强机理,并根据体系中不同的结构关系分别总结了聚合物/未改性纳米粒子复合体系和聚合物/聚合物接枝纳米粒子复合体系中影响力学性能的因素. 该部分内容具有重要的理论和实践意义,有助于构建复合体系微观结构与宏观性能之间的关系,进而对微观层面调控PNCs的力学性能提供指导.  相似文献   

5.
飞行时间质谱仪(TOFMS)在理论上无质量范围的限制,可实现大分子蛋白质与核酸的非共价复合物的直接检测.特别是在近中性溶液条件下通过对芥子酸和6-氮杂-2-硫代胸腺嘧啶基质的使用及双层样品制备方法的改善,获得了稳定复合物的高灵敏度质谱检测.肌红蛋白-血红素复合物能够在芥子酸基质的不同pH条件下(pH2.0或pH5.0)同时观察到.而运用双层样品制备方法,获得了核糖核酸酶复合物(RNaseS)在第一次激光照射下的突出质谱峰,但其丰度均随更多的激光打击而减弱.  相似文献   

6.
在MP2/aug-cc-pvdz水平下,对二体氢键复合物H2O…HCCO(Ⅰ)和HCCO…H2O(Ⅱ)以及三体氢键复合物(H2O)2…HCCO(Ⅲ),H2O…H2O…HCCO(Ⅳ)和H2O…HCCO…H2O(Ⅴ)的几何和相互作用能进行了计算.轨道分析表明Ⅲ中HCCO中的H(1),C(2)通过2个氢键与2个水分子形成了环...  相似文献   

7.
柳东芳  郭志新  李媛  朱道本 《化学通报》2002,65(11):727-733
本文从实验以及理论研究两方面介绍了C60与叠氧化合物的单加成反应。依照叠氮化合物的不同,C60与叠氮合物的单加成反应可分为烷基叠氮化物与C60的反应,酰基叠氧化物与C60的反应以及苯基叠氮化与C60的反应三类,而反应产物则为C60亚氨基[6,6]闭环衍生物和C60亚氨基[5,6]开环衍生物两类,不同类型的反应具有不同的反应机理,某些C60亚氨基[5,6]开环衍生物可以转化为C60亚氨基[6,6]闭环衍生物。本文还介绍了碳纳米管与叠氮化合物的加成反应。  相似文献   

8.
成功合成并分离出两例不对称C60-三聚茚复合物分子,利用高分辨质谱、元素分析,核磁共振氢谱、碳谱对化合物的结构与纯度进行了表征;利用紫外光谱、循环伏安曲线对化合物的电子结构进行了表征。结果表明: C60-分子与三聚茚结合后表现出较为明显的分子内电子转移,证明扩展共轭体系对分子的共轭性有较为明显的调控作用。  相似文献   

9.
壳聚糖维生素C复合物的合成及性能   总被引:1,自引:0,他引:1  
通过离子间静电引力作用合成了壳聚糖维生素C复合物。采用红外光谱和差热分析测试技术表征了复合物的结构。溶解度测定结果表明,该复合物具有水溶性。邻苯三酚自氧化速率测定结果表明,该复合物对.O2-的清除作用优于壳聚糖。  相似文献   

10.
蛋白质相互作用的研究方法   总被引:1,自引:0,他引:1  
孙宇  贾凌云  任军 《分析化学》2007,35(5):760-766
生物体的生理功能主要由细胞中的蛋白质控制和调节。其中,多数蛋白质是通过与配体结合或是作为蛋白质复合物中的一部分参与细胞的代谢过程。因此,研究蛋白质间的相互作用是理解生命活动的基础。本文对现有蛋白质相互作用的研究方法和技术进行了评述。  相似文献   

11.
The reaction barriers of (He+C60(He@60)) have been calculated by the quantum-chemical method EHMO/ASED in the following four paths: (1) penetrate through the pentagon on the C60 cage; (2) penetrate through the hexagon on the C60 cage,(3) penetrate through the short bond; (4) penetrate through the long bond. Corresponding to each path, there are two choices: (a) while He penetrate C60 cage, the distances of the C’s which are the most adjacent to He are changed with a planar extension and a concerned window is formed; (b) while He penetrate C60 cage, the distances of the C’s which are the most adjacent to He are changed with a spherical extension and a concerned window is formed. The results are given in Figs. 1-2 and Tables 1-2. It is shown that the reaction through path(4) with choice (a) has the least reaction barrier, being optimum. At that case, a window of 9-membered ring is formed. Because the window extension of C6H6 is more free than that of C60, the barrier of He penetrating through C6H6 will be lower than that of He penetrating through C60.  相似文献   

12.
The microdisk electrode voltammetric behaviors of C_(60) are reported in this communication. This was accomplished by use of a mixed solvent system as Acetonotrile:Xylene=1:4 and a supporting electrolyte as 0.1 mol·L~(-1) Bu_4NPF_6. Au, Pt and Hg (Pt) were used as working electrode. In this new conditions, the successive six step reduction of C60 were obtained at below 15 ℃. It was found that the former five steps are all the single electron reversible reduction, but behaviors of the sixth steps are like EC' processes. Several electrochemical data were determined.  相似文献   

13.
Raman spectroscopy was applied to characterize the species deposited from the mass-selected C60 ion beam which was accelerated to 900 eV. The substrates for the deposition were (0001) surface of highly oriented pyrolitic graphite and (111) surface of gold crystal. The species do not exhibit the Raman scattering features of buckminsterfullerene, but displays peaks at 1585 and 1332 cm-1 instead. The former peak is the chararteristic Ranan peak of hexagonal graphite, and the latter can be attributed to the amorphous carbon in sp3 hybridization. The result reveals that C60 was collapsed to form a new phase when it collides on the solid surface.  相似文献   

14.
Mass-selected C60 beam produced by laser ablation was accelerated and bombarded the (0001) surface of highly oriented pyrolitic graphite and (111) surface of gold single crystal. The samples were characterized by STM. The STM images showed that, the deposited species collapsed and formed planar structure on the solid surface, but the collapsed species were not dissociated and well oriented on the surface. Both positive and negative C60 ions were observed in the desorption mass spectra, confirming that the species collapsed on the solid surface are still the C60 clusters.  相似文献   

15.
通过全甲基化环糊精和卟啉之间的\"Click\"反应,合成了一种不对称环糊精修饰的卟啉衍生物,并对其结构进行了表征.该化合物与氯金酸作用可以形成平均粒径为5 nm的水溶性金纳米粒子,该金纳米粒子进一步与C60作用形成网状纳米聚集体,并通过紫外光谱和透射电子显微镜验证了聚集体的结构.  相似文献   

16.
ZrO2表面B2O3的分散及其作用状态   总被引:4,自引:0,他引:4  
用XPS、FT IR和FT Raman等技术研究了ZrO2表面B2O3的分散及其作用状态,测定了B2O3在ZrO2表面的分散阈值.结果表明:B2O3在ZrO2表面可以三配位BO3和四配位BO4结构单元存在;载体ZrO2的预焙烧温度和硼含量对B2O3的分散及作用状态有较大影响,并改变BO3与BO4结构单元之间的比例.实验测得B2O3在ZrO2载体上的单层分散阈值为0.05 gB2O3/gZrO2(或B2O3的质量分数w=4.76%),处在此单层中的硼原子以BO4为结构单元直接与ZrO2表面相作用.只有当B2O3的负载量超过此(单层)分散阈值时, BO3结构单元才会形成.  相似文献   

17.
A recent experimental determination[1] of the dissociation energies (D0) for H2N-H, H2N+-H and H2N-H+, the ionization energies for NH3 and NH2 resulted in large deviations when compared with those of the earlier values and the QCISD(T)/6-311+G(3df,2p) ab initio calculations. We have performed some higher level ab initio calculations on these data by utilizing the Gaussian 92/DFT and Gaussian 94 pakages of programs and have assessed the available experimental values. Our calculations were carried out at the QCISD (TQ)/aug-cc-pVDZ, G2(QCI), QCISD(T)/6-311 ++G(3df,3pd) and QCISD(T)/aug-cc-pVTZ levels of theory. Geometries were optimized at both of the MP2(full)/6-31G(d) and the MP2(full)/6-31(d,p) levels, and were compared with those of the experiments if available. The MP2(full)/6-31G(d,p) tight-optimized geometries for the neutrals are closer to those of the experiments than those of the MP2 (full)/6-31G(d), and are in excellent agreement with the experimental results as shown in Table 1. In this case, we assumed that the optimized geometries for the cations would be better if p polarization functions are added to the hydrogen atoms. We firstly noted that the symmetry of the NH3+ cation was D3h, other than Cs. as reported in ref.[1]. All of the zero-point energies and the final geometries are calculated at the MP2(full)/6-31G(d,p) level of theory. We have also repeated the QCISD(T )/6-311 + G(3df,2p) calculations of ref. [1], because we could not identify their level of goemetry optimization. It is found that the total energy, -55.244 19 Hartrees, for NH2+(1A1 ) in ref.[1] might be in error. Our result is -55.336 29 Hartrees at the same level of theory. At our highest level [QCISD(T)/aug-cc-pVTZ] of calculations as shown in Table 3, the D0 (temperature at zero Kelvin) values of H2N-H, H2N+-H(3B1for NH2+ ) and H2N- H+ are 4.51, 5.49 and 8.00 eV, respectively. These data reported in re f.[1] were 4.97, 5.59 and 8.41 eV, respectively. Our result on D0(H2N-H) supports the work of ref.[2,3,5,6]. The ionization energies (IE) for NH3 and NH2 (3B1 for NH2+) at our highest level are 10.11 and 11.09 eV while in ref.[1] were 10.16 and 10.78 eV, respectively. For the latter, our result supports the experiment of ref.[3]. Our predicted D0 for HN2+-H and IE for NH2 (1A1 for each NH2+) are 6.80 and 12.39 eV, respectively. These values differ greatly from the predicted values (9.29 and 14.88 eV) of ref.[1] where the total energy of NH2+(1A1) might be in error. The D0 value for HN-H has not been found in ref.[1]. Our result supports the work of ref.[3]. We have also derived all of these values at the temperature of 298K and under the pressure of 101kPa at several levels of thoery as shown in Table 3. On examining the experiment of ref.[1] in detail, it is easy to find that all of the larger deviations might be from a too high value of the appearance potential of proton AP(H+). Indeed, ref.[1] has mentioned that the determintion of AP(H+), due to kinetic shift, would lead to a hihger value for the dissociation energy as has been pointed out by Berkowitz and Ruscic. In this work, we concluded that, besides some mistakes in the theoretical calculations of ref.[1], the dissociation energies for H2N-H and H2N-H+,the IE for NH2 (3B1 for NH2+) might also be unreliable and need to be re-examined.
  相似文献   

18.
在CCSD(T)/aug-cc-pVTZ&;CEP-121G//B3LYP/6-311+G(d)&;LANL2DZ水平上, 研究了由更高周期的Sn和Pb单掺杂Al4团簇形成的五原子含铝体系XAl4(X=Sn, Pb), 确定了体系的低能异构体, 分析了关键异构体的结构和稳定性. 研究结果表明, 与SiAl4及GeAl4的基态平面四配位Si/Ge结构所不同, 等价电子的SnAl4和PbAl4体系的基态结构不是平面四配位Sn/Pb, 而是平面四配位Al, 其中杂原子Sn/Pb采取二配位方式, 此外, Sn/Pb采取三配位方式的非平面结构的稳定性也要优于平面四配位Sn/Pb结构.  相似文献   

19.
合成了一系列含N-杂环卡宾二硫化碳加合物配体的锰铼金属有机化合物,其中包括3种单核化合物和3种双核化合物,对它们的结构进行了表征,并研究其反应性和电化学性质. 与三烷基膦二硫化碳配体相比,含N-杂环卡宾二硫化碳加合物配体的锰铼金属有机化合物展现出不同的反应特性. 研究结果表明,[MnRe(CO)6(μ-H){μ-CH3SC(S)IMes2}]配合物具有催化质子还原成氢气的能力.  相似文献   

20.
C12-s-C12•2Br和C12En混合水溶液的胶团化行为   总被引:3,自引:0,他引:3  
季铵盐二聚表面活性剂C12 s C12•2Br(s=2、3、4、6)和非离子表面活性剂C12E10或C12E23在水溶液中生成混合胶团.其临界胶团总浓度cmcT值介于二元复配体系中各组分的临界胶团浓度和之间.当添加少量非离子型表面活性剂(在水溶液中的摩尔分数α2=0.1)时,混合胶团中C12E10或C12E23的摩尔分数均已超过0.35;随着溶液中非离子型表面活性剂含量的增大,混合胶团中逐渐以C12E10或C12E23成分为主.  相似文献   

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