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651.
P. A. Troshin O. V. Boltalina N. V. Polyakova Z. E. Klinkina 《Journal of fluorine chemistry》2001,110(2):157-163
We have recently developed methods of preparation of fluorofullerenes with specific fluorine content. Our previous successful synthesis of C60F36 and C60F18 with the use of transition metal fluorides inspired us to probe other high oxidation metal fluorides. In this work we report on the use of the binary lead fluorides (PbF2, PbF4, Pb2F6) and their complexes with alkali metal and alkaline earth metal fluorides (M2PbF6, M3PbF7 and M′PbF6) as fluorinating reagents for fullerenes. 相似文献
652.
Xian-yu Deng Li-ping Zheng Yue-qi Mo Gang Yu Wei Yang Wen-hua Weng Yong Cao Institute of Polymer Optoelectronic Material Devices South China University of Technology Wuhan China 《高分子科学》2001,(6):597-602
Recent work demonstrated that efficient solar-energy conversion could be achieved in polymer photovoltaic cells(PVCs) based on interpenetrating bi-continuous networks. In this paper we present a comprehensive study on improvingenergy conversion efficiencies of PVCs based on composite films of MEHPPV and fullerene derivatives. Carrier collectionefficiency of ca. 30% el/ph and energy conversion efficiency of 3.9% were achieved at 500 nm. At reverse bias of 15 V, thephotosensitivity reached 0.8 A/W, corresponding to a quantum efficiency over 100% el/ph. These results suggest that highefficiency photoelectric conversion can be achieved in polymer devices with M-P-M structure. These devices are promisingfor practical applications such as plastic solar cells and plastic photodetectors. 相似文献
653.
富勒烯有着独特的球形结构,这一结构赋予了其优异的光电及生物性能,在生物医药领域备受关注。环糊精具有良好的水溶性和生物相容性,锥筒状结构赋予了其特异性包合作用,在主客体化学中有着非常重要的地位。富勒烯/环糊精的复合物,结合了富勒烯和环糊精的优势,在DNA切割,光动力学疗法,药物载体等领域发挥了重要作用。本文从富勒烯与环糊精体系的构筑出发,综述了富勒烯/环糊精非共价包合物及共价偶联物在生物医药领域应用的研究进展,且对富勒烯/环糊精复合物的应用进行了展望,为构建新型富勒烯/环糊精复合物提供参考。 相似文献
654.
新型共价键连的富勒烯-卟啉化合物的合成与表征 总被引:1,自引:0,他引:1
为了构造一个具有有效电荷转移的给-受体体系,通过1,3-偶极加成反应,由5-[2-'(4″-醛基苯氧丙氧苯基)]-10,15,20-三苯基卟啉(H2P-CHO)、肌氨酸和C60首次合成了一种新的以共价键相连的富勒烯-卟啉配体(H2P-C60),同时用该配体制备了其锌配合物(ZnP-C60),并用红外光谱、元素分析、电子光谱、核磁共振氢谱和质谱等方法进行了表征. 相似文献
655.
The AM1 semiempirical calculation method was employed to study the structures and electronic properties of a series of isoxazolo fullerene derivatives. Based on the AM1 geometry optimization, the electronic spectra of molecules were studied by using ZINDO/CIS methods. The results indicated the HOMO LUMO energy gaps of those isoxazolo fullerenes were lower than that of C60. There existed the intramolecular electron transfer from the additional section to C60 moiety. The electronic spectrum data showed that the exception of the absorption was beyond 400 nm.The results were in good accordance with the experiment results. Nonlinear optical susceptibilities α, β and γ of molecules were calculated according to Finite Field(FF)/AM1, and the influence of molecular structures on nonlinear optical properties was examined. 相似文献
656.
将常用的有机催化剂如N,N′-二环乙基碳二亚胺、4-二甲氨基吡啶和1-羟基苯并三唑用于亚甲基「60」富勒烯羧酸的经典酯化反应,没有得到所期待的哑铃形偶联物,而得到单亚甲基富勒烯乙基酯,用柱色谱分离的产物经MALPI和FT-IR证实,并提出可能的反应机理。 相似文献
657.
使用密度泛函理论(DFT)-B3LYP/6-31G*方法研究了B、N、Si、P和Co在C50和C70中的掺杂能和电子结构, 并基于曲率理论和电子结构探讨了掺杂富勒烯的结构稳定性. 计算结果表明, 掺杂能随着原子曲率的增大而减小, 随着掺杂物种原子半径的增大而增大, B、N、P和Co的掺杂有利于C50结构的稳定, 而B和N的掺杂不利于C70结构的稳定; 除了用于反映原子活性的曲率主要决定掺杂反应性, 各不等价碳原子在C50和C70的最高占据分子轨道(HOMO)中所占成分对掺杂能的影响也很大, 且其成分越大越有利于掺杂. 此外, 掺杂原子得失电子情况与其电负性有关. 本工作将为富勒烯结构稳定性的研究提供理论依据. 相似文献
658.
Andrzej Graja Iwona Olejniczak Andrzej Bogucki Davide Bonifazi Fran ois Diederich 《Chemical physics》2004,300(1-3):227-232
Solid-state electronic (UV–Vis) and vibrational (IR) spectra of several fullerene–porphyrin conjugates were recorded in KBr in the spectral range between 400 and 50,000 cm−1. It was observed that significant redistribution of the charges occurs in both fullerene and porphyrin moieties upon covalent linkage. This effect is mainly observed as shifts of both electronic and vibrational bands in comparison with the respective free porphyrin and fullerene features. Variable temperature IR measurements were also performed. 相似文献
659.
660.
Panagiota Sofou Eugenia Panou-Pomonis Vassilios Tsikaris Maria Sakarellos-Daitsiotis Fernando Formaggio 《Tetrahedron》2004,60(12):2823-2828
A proline-rich [60]fullerene peptide was synthesized by use of (i) a 1,3-dipolar cycloaddition of an N-substituted glycine derivative to [60]fullerene, (ii) esterification of the isolated alcohol with the C-terminal amino acid of the desired peptide sequence, and finally (iii) coupling of the remaining hexapeptide to give the final product 8 as a TFA salt, with oxidized methionine. Product 8 was found to be biologically active against sera from MCTD and SLE patients (ELISA experiment). 相似文献