利用给体-π-受体分子模板在Au(111)电极表面构筑富勒烯带状结构(英文)

富勒烯与功能分子之间的电荷作用已经被广泛应用于功能性器件的构筑中.这些功能器件的性能与电极表面的薄膜排布结构有着密切关系.因此,研究电极表面的富勒烯和功能分子的组装结构对这些器件的构筑和功能的发挥有着重要意义.本文利用电化学扫描隧道显微镜技术,在HClO4溶液中系统研究了C60分子与有机电子给体-π-受体分子C16H33O-I3CNQ[Z-β-(5-hexadecyloxy-1,3,3-trimethyl-2-indolium)-α-cyano-4-styryl dicyanomethanide]在Au(111)电极表面的二维组装结构.研究发现:C16H33O-I3CNQ分子在Au(111)电极表面组装形成具有短程有序性的条陇状结构;而C60分子在C16H33O-I3CNQ模板之上组装形成了带状结构.C60分子带状结构的形成方向受到了C16H33O-I3CNQ分子中电子给体-π-受体部分排列结构的影响.C60分子与C16H33O-I3CNQ分子之间的π-π堆积作用和电荷转移作用对这种带状结构的形成有着密切关系.这一结果为利用富勒烯和功能分子之间的作用构筑功能器件提供了一种新的制备方法.     

富勒烯C60-多芳胺类衍生物选择性加成反应的研究

多芳胺是良好的电子给体,富勒烯C60作为电子受体的光诱导分子内和分子间电荷转移现象[1,2]引起人们普遍关注,尤其是设计合成长寿命电荷分离态的富勒烯C60-多芳胺基类衍生物研究[3,4]是热点课题之一.由于聚吡咯/聚芳胺的氧化还原电位较低[5],我们设想包含吡咯/芳胺给体的富勒烯C60衍生物能延长电荷分离态的寿命.本文用1,3-偶极环加成反应[6]对富勒烯C60与多芳胺化合物的选择性加成反应进行了研究,在不同条件下得到了单加成产物和三加成产物,用FAB-MS,UV-vis,IR,1H NMR,13C NMR,HPLC等方法确定了其分子结构.并且利用半经验AM1量子化学方法在理论上研究了它们的优化构型(如图1)、电子结构,结果表明,富勒烯C60-多芳胺基类衍生物的前沿轨道主要由富勒烯C60部分决定,富勒烯C60母体与功能化基团三苯胺基之间存在较强的分子内电荷转移,这为富勒烯C60衍生物作为光电分子器件材料的应用提供了理论和实验依据.     

富勒烯稠合体与共轭聚合物作为有机太阳能电池材料的研究进展

介绍了有关富勒烯与共轭聚合物超快光诱导电子的研究状况和三种不同光敏层材料制备的太阳能电池的组装和性能,包括:(1)以共轭聚合物/C60或C60衍生物的主体异介质为光敏层,(2)分子水平上的主体异介质:D-A双功能聚合物,(3)单纯以富勒烯稠合体为光敏层,以及国内外这三种太阳能电池研究的进展情况及存在的问题.     

化学高考总复习单元练习三 基本概念 基本理论(B)

第Ⅰ卷（选择题,共84分）一、选择题（每小题3分,共15分。每小题只有一个选项符合题意）根据以下叙述,回答1～2小题。1996年诺贝尔奖授予发现C60分子的两位化学家。C60具有空心的类似于足球状结构,在C60分子的球表面上存在共轭双键（类似1,3-丁M烯中的C＝C—C＝C）,因而被称为巴基球或足球烯或富勒烯。现以富勒烯为它的正式名称。富勒烯及其化合物有很多优良性能,在催化、润滑、治癌、贮氢以及半导体材料等方面有广阔的前景。1．富勒烯与金刚石、石墨的相互关系是（）A．同系物B．同分异构体C．碳的同位素D．碳的同素异形体2．…     

C60吡咯烷键联2-(5-溴)噻吩的设计合成研究

富勒烯C60键联光活性、电活性有机功能基团获得性能优异的富勒烯C60衍生物是目前研究十分活跃的领域[1].多聚噻吩是良好的有机导体,具有高导电性能、电致发光性能等,利用其与富勒烯键联获得具有电学、磁学及生物学特性的分子,有望成为一种新型的分子器件材料.     

密度泛函理论和从头算方法对富勒烯分子静电势的比较研究

分别在Hartree-Fock和密度泛函B3LYP理论下,用6-31G*基组研究了C60和C70分子的静电势,比较了这方法计算得到上述分子静电势值的大小,静电势图形和静电势差值曲线,分析了富勒烯的电子相关效应.     

富勒烯配合物η2-C60[Ru(NO)(PPh3)]2的合成与表征

从1985年Kroto等[1]发现富勒烯至今, 其在化学、材料和物理等领域已有较多的研究[2～8]. 目前有关C60取代的金属小分子配合物(如羰基、亚硝酰基等)的研究方兴未艾. 而以NO为配体的亚硝酰基金属富勒烯配合物仅有数例[2,3], Green等[3]在研究以CO和NO为配体的金属富勒烯系列化合物的合成中, 认为C60不能与Ru(NO)2(PPh3)2发生反应. 本文利用Ru(NO)2(PPh3)2与C60反应首次合成出η2-C60[Ru(NO)(PPh3)]2配合物, 并对其进行了表征.     

［60］富勒烯硫桥键联1,3-二硫杂环戊烯基-2-硫酮衍生物的理论研究及合成和表征

摘要为了获得具有长寿命电荷分离态的［60］富勒烯-富硫衍生物有机功能分子, 我们设计了用单键硫桥键联［60］富勒烯和硫酮衍生物的分子7和8, 用半经验AM1方法得出最低能量的几何结构, 在此基础上用密度泛函(DFT) B3LYP/3-21G方法,对其进行计算, 得出电子相关的优化参数, 预测其稳定性. 发现用硫桥链接后, 硫酮部分和C60部分之间的距离比文献报道的无硫桥链接的C60衍生物要短, 且能隙变小, 使得在光激发下形成激发态较容易. 同时用硫酮烯砜6与C60发生Diels-Alder环加成反应, 合成了这两个新化合物, 用TOF-MS， 1H NMR， 13C NMR, IR， UV-Vis和荧光光谱等进行了结构表征.     

内嵌金属碳氮化物团簇富勒烯的稳定性与生成机理

对新结构富勒烯金属包合物的探索是富勒烯领域中的研究重点。本文从内嵌团簇与富勒烯碳笼尺寸匹配的角度出发,对基于金属碳氮化物团簇的新结构富勒烯金属包合物进行了研究。通过量子化学计算研究了M_3NC团簇(M=Y,La,Gd)内嵌在D_2(186)-C_(96)和D_2(35)-C_(88)分子中所形成包合物的稳定性和电子结构,发现富勒烯碳笼接受内嵌团簇转移的六个电子形成了稳定结构。结合文献已报道过的Sc_3NC@I_h(7)-C_(80)分子,阐明了M_3NC团簇与富勒烯碳笼之间的尺寸匹配效应,并发现D_2(186)-C_(96)、D_2(35)-C_(88)和I_h(7)-C_(80)三种富勒烯碳笼均具有五元环均匀分布的结构特点。我们对富勒烯之间的转变路径进行了研究,提出了不含Stone-Wales异构化过程的富勒烯直接生成机理,即可以通过增加碳原子的过程使五元环重排,在保持稳定性结构单元的同时转变为更大碳笼。     

C_(60)二取代化合物与环状二卟啉相互作用研究

通过紫外-可见吸收光谱研究了环状二卟啉与trans-2,trans-3,trans-4和e型4种吡咯烷二取代C60衍生物(bis-C60)异构体之间的弱相互作用。研究表明,吡咯烷取代基团的引入使富勒烯与二卟啉的结合常数按C60单取代C60二取代C60的顺序降低。4种bis-C60与二卟啉的结合常数变化顺序为trans-2trans-3≈trans-4e,表明2个取代基间的相对位置对二取代C60与环状二卟啉间作用有一定影响,分析认为主、客体分子间空间位阻效应的差异是导致这一变化的主要原因。以trans-3 bis-C60/二卟啉复合物为代表,通过密度泛函理论模拟了其几何结构和吸收光谱。     

Semiempirical molecular dynamics studies of C60/C70 fullerene oxides: C60O, C60O2 and C70O

The spectral analysis indicates that all isomers of C₆₀O, C₇₀O and C₆₀O₂ have an epoxide-like structure (an oxygen atom bridging across a C–C bond). According to the geometrical structure analysis, there are two isomers of fullerene monoxide C₆₀O (the 5,6 bond and the 6,6 bond), eight isomers of fullerene monoxide C₇₀O and eight isomers of fullerene dioxide C₆₀O₂. In order to simulate the real reaction conditions at 300 K, the calculation of the different isomers of C₆₀O, C₆₀O₂ and C₇₀O fullerene oxides was carried out using the semiempirical molecular dynamics method with two different approaches: (a) consideration of the geometries and thermodynamic stabilities, and (b) consideration of the ozonolysis mechanism. According to the semiempirical molecular dynamic calculation analysis, the probable product of this ozonolysis reaction is C₆₀O with oxygen bridging over the 6–6 bond (C_2v). The most probable product in this reaction contains oxygen bridging across in the upper part of C₇₀ (6–6 bond in C₇₀O-2 or C₇₀O-4) an epoxide-like structure. C₆₀O₂-1, C₆₀O₂-3 and C₆₀O₂-5 are the most probable products for the fullerene dioxides. All of these reaction products are consistent with the experimental results. It is confirmed that the calculation results with the semiempirical molecular dynamics method are close to the experimental work. The semiempirical molecular dynamics method can offer both the reaction temperature effect by molecular dynamics and electronic structure, dipole moment by quantum chemistry calculation.     

Conformational isomers and isomerization of group 6 (Cr, Mo, and W) metal-bis(toluene) sandwich complexes probed by variable-temperature electron spectroscopy

Group 6 metal (Cr, Mo, and W)-bis(toluene) sandwich complexes are synthesized in a laser-vaporization molecular beam source. Conformational isomers and isomerization of these complexes are studied by variable-temperature pulsed-field-ionization zero-electron-kinetic-energy spectroscopy and density functional theory. For Cr-bis(toluene), four rotational conformers are identified with methyl-group dihedral angles of 0, 60, 120, and 180°. The ground electronic states of these conformers are (1)A(1) (C(2v), 0°), (1)A (C(2), 60 and 120°), and (1)A(g) (C(2h), 180°) in the neutral form and (2)A(1) (C(2v), 0°), (2)A (C(2), 60 and 120°), and (2)A(g) (C(2h), 180°) in the singly charged cationic form. For Mo- and W-bis(toluene), the four rotamers are resolved into three (0, 60/120, and 180°) and two (0 and 60/120/180°) groups, respectively. For all three metal sandwiches, the most stable conformer is in the complete eclipsed configuration (0°) and has the highest ionization energy. The conversion from 60/120/180° to 0° rotamer is observed from helium to argon supersonic expansions and is more efficient for the heavier Mo and W species.     

Ab initio calculation of carbon clusters. II. Relative stabilities of fullerene and nonfullerene C24

Chemical stabilities of six low-energy isomers of C24 derived from global-minimum search are investigated. The six isomers include one classical fullerene (isomer 1) whose cage is composed of only five- and six-membered rings (56-MRs), three nonclassical fullerene structures whose cages contain at least one four-membered ring (4-MR), one plate, and one monocyclic ring. Chemical and electronic properties of the six C24 isomers are calculated based on a density-functional theory method (hybrid PBE1PBE functional and cc-pVTZ basis set). The properties include the nucleus-independent chemical shifts (NICS), singlet-triplet splitting, electron affinity, ionization potential, and gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO-LUMO) gap. The calculation suggests that the neutral isomer 2, a nonclassical fullerene with two 4-MRs, may be more chemically stable than the classical fullerene (isomer 1). Analyses of molecular orbital NICS show that the incorporations of 4-MRs into the cage considerably reduce paratropic contributions from HOMO, HOMO-1, and HOMO-2, which are mainly responsible for the sign change in NICS from positive for isomer 1 (42) to negative (-19) for isomer 2, although C24 clusters satisfy neither 4N+2 nor 2(N+1)2 aromaticity rule. Anion photoelectron spectra of four cage isomers, one plate, one monocyclic ring, and one tadpole isomer, as well as three bicyclic ring isomers are calculated. The simulated photoelectron spectra of mono- and bicyclic rings (with C1 symmetry) appear to match the measured HOMO-LUMO gap (between the first and second band in the experimental spectra) [S. Yang et al., Chem. Phys. Lett. 144, 431 (1988)]. Nevertheless, the nonclassical fullerene isomers 3 and 4 apparently also match the measured vertical detachment energy (2.90 eV) reasonably well. These results suggest possible coexistence of nonclassical fullerene isomers with the mono- and bicyclic ring isomers of C24(-) under the experimental conditions.     

Photoelectron spectroscopy and electronic structures of fullerene oxides: C60Ox- (x = 1-3)

We report a photoelectron spectroscopy (PES) study on a series of fullerene oxides, C60Ox- (x = 1-3). The PES spectra reveal one isomer for C60O-, two isomers for C60O2, and multiple isomers for C60O3-. Compared to C60, the electronic structures of C60Ox are only slightly perturbed, resulting in similar anion photoelectron spectra. The electron affinity of C60Ox was observed to increase only marginally with the number of oxygen atoms, x, from 2.683 eV for C60, to 2.745 eV for C60O, and 2.785 eV/2.820 eV for C60O2 (two isomers). We also carried out theoretical calculations, which confirmed the observed isomers and showed that all the fullerene oxides are in the form of epoxide. The PES and theoretical calculations, as well as molecular orbital analysis, indicate that addition of oxygen atoms to the C60 cage only modifies the local carbon network and leave the rest of the fullerene cage largely intact geometrically and electronically.     

Photochemical and photophysical properties of three carbon-bridged fullerene dimers: C121 (I, II, III)

The photochemical and photophysical properties of the three C121 isomers (I, II, III) were investigated with MADLI-TOF-MS, UV-vis spectra, fluorescence spectra, absorption spectra of their DMA complexes, and theoretical calculations. The three isomers of C121 (I, II, III) have different stabilities under laser irradiation, but isomer I and isomer II show good stability against the heat-induced conversion between different isomers: No conversion between the isomers was found after heating the mixture of isomer I and isomer II at 353 K for 12 h in Ar atmosphere. The results of UV-vis absorption and fluorescence spectra indicate that interactions between two C60 moieties of C60=C=C60 in the ground and singlet states are not significant, C121 (I, II, III) behaves as an electron-acceptor similar to C60. These indicate that the formation of the fullerene chain structure (e.g., C60=C=C60) does not disturb the photochemical and photophysical properties of the C60 monomer itself, even that the properties were enhanced by the formation of the polymer. This is significant for the C60 polymer in photochemical or photoelectronic applications in which C60=C=C60 can be an excellent basic unit of polymers.     

Thermodynamic rearrangement synthesis and NMR structures of C1, C3, and T isomers of C60H36

The structures of three C60H36 isomers, produced by high-temperature transfer hydrogenation of C(60) in a 9,10-dihydroanthracene melt, was accomplished by 2D (1)H-detected NMR experiments, recorded at 800 MHz. The unsymmetrical C(1) isomer is found to be the most abundant one (60-70%), followed by the C(3) isomer (25-30%) and the least abundant T isomer (2-5%). All three isomers are closely related in structure and have three vicinal hydrogens located on each of the 12 pentagons. Facile hydrogen migration on the fullerene surface during annealing at elevated temperatures is believed to be responsible for the preferential formation of these thermodynamically most stable C60H36 isomers. This hypothesis was further supported by thermal conversion of C60H36 isomers to a single C(3v) isomer of C60H18.     

电场作用下C60富勒烯二聚体分子的几何构型与失效

By the molecular mechanics/quantum mechanics method, the geometry distortion and configuration invalidity of dimmer C60fullerene (2C60) molecule in external electric field are simulated. The effect of the electric field, with three different directions, on geometry distortion, configuration invalidity, polarization charge distribution and dipole moment for 2C60 molecule is discussed systemtically. Further the geometry distortion and invalidity of 2C60 molecule are respectively compared with those of C60 fullerene molecule in electric field. By comparison, it is shown that geometry distortion and configuration invalidity behavior of 2C60 molecule are sensitive to the direction of electric field, when the directions of the applied electric field are parallel to the bridged C-C bonds. For 2C60molecule it is very easy for the configuration of 2C60 molecule to be invalidated and the invalidity mode is very particular as well.     

C_(59)F_(2n)HN(n=1,2)异构体的结构与稳定性的理论研究

分别用MNDO和AM1两种半经验方法,对C59F2nHN (n = 1, 2) 的异构体进行几何构型全优化,结合频率分析及HF/6-31G单点能计算,确定了各异构体的基态结构及其相对稳定性。计算结果表明,C59HN的F加成物的立体选择性规律与C60的不同,最稳定异构体不是1-2加成物。C59F2HN的最稳定异构体是1-4加成的6, 18-或12, 15-异构体; C59F4HN的最稳定异构体是1-4,1-4加成的6, 18; 12, 15-异构体,其能量远小于其它各异构体的能量。N原子取代碳笼骨架C原子后,改变了碳笼F加成物的立体选择性规律。     

C_(60)侧链线性聚硅氧烷毛细管气相色谱固定相的制备与色谱性能

首次以含氢硅油依次与溴丙烯、叠氮钠及Ｃ６０反应合成了两种新的Ｃ６０侧链线性聚硅氧烷并用作毛细管气相色谱固定相。该类固定相柱效高,使用温度范围宽,热稳定性好,最高柱温达３６０℃,基线漂移量为３０～４０ｆＡ,呈弱极性,对各种醇、酮、芳胺、多环芳烃、邻苯二甲酸酯类有良好的分离选择性,尤其对各类位置异构体有着独特的分离效果。     

Geometric and electronic structures of metal-substitutional fullerene C59Sm and metal-exohedral fullerenes C60Sm

The geometric and electronic structures of metal-substituted fullerene C59Sm and exohedral fullerenes C60Sm are studied using the density-functional theory. The geometric optimization shows that the replacement of a C atom with a Sm in C60 yields a stable substitutionally doped fullerene C59Sm, and among the five possible optimized geometries for C60Sm, the most favorable exohedral sites are above the center of a hexagon and a pentagon ring. The calculations for electronic structures show that the magnetic moment of Sm is preserved for all the stable structures as tiny hybridization takes place between the orbitals of the Sm atom and those of their neighboring carbons. Because of the small energy gaps and the half occupation of the highest occupied molecular orbitals, all the stable C60Sm isomers are inferred to be conductors.