共查询到20条相似文献,搜索用时 15 毫秒
1.
K. P. Meletov V. K. Dolganov Yu. A. Ossipyan 《Molecular Crystals and Liquid Crystals》2013,570(1):915-920
Abstract The absorption spectra of the C60 and C70 are measured at pressures up to 19 GPa. The pressure dependence of the fundamental absorption edge position E(P) is determined for both materials. The initial value of dE/dP=?0.15 eV/GPa for the stronger-absorption region of C60 decreases up to ?0.019 eV/GPa at 12 GPa. The weaker-absorption region located near the fundamental absorption edge shifts slower dE/dP=?0.05 eV/GPa. For the C70 the initial value of dE/dP=?0.1 eV/GPa decreases up to ?0.029 eV/GPa at 10 GPa. All pressure induced changes are reversible in this pressure range. 相似文献
2.
Takashi Itoh Ryo Yasuda Takayuki Go Shoji Nitta Shuichi Nonomura 《Molecular Crystals and Liquid Crystals》2013,570(1):661-666
Abstract The intercalation of O2 in C60 and C70 solids have been studied. In both gas effusion spectra of C60 and C70 powder exposed to O2 at room temperature, two evolution peaks of O2 are found near 80 and 150°C. In both C60 and C70 powder, the peak near 80°C does not depend on a heating ratio and the peak near 150°C shifts to higher temperature with the heating ratio. The activation energy on diffusion of O2 in C60 and C70 solids are ~0.27eV and ~0.46eV, respectively. The number of O2 intercalated in C70 powder is larger than that in C60 powder. Electron spin density of 02-intercalated C60 film is larger than that of C70 film. The effect on the properties of C60 and C70 solids by the intercalation of O2 are discussed. 相似文献
3.
Abstract The X-band ODMR of C70 molecules isolated in a toluene/polystyrene (C70:T/PS) glass and C70 films is compared to that of C60. As C60:T/PS, the C70 glasses exhibit only a triplet pattern at g ? 2, clearly due to an exciton delocalized over the molecule; however, it is strikingly asymmetric and narrower, due to the larger size of C70. The ODMR of both C60 and C70 films includes a narrow photoluminescence-enhancing polaron resonance and full- and half- field narrow and broad triplet exciton patterns. As in the glasses, the narrow pattern is due to the exciton delocalized over the molecule and is narrower in C70 The broad pattern is tentatively assigned to a triplet localized on a face adjacent to a neighboring molecule. In contrast to C60, the ODMR of C70 films is detectable up to 295 K, apparently due to the slower rotation. 相似文献
4.
Kenji Ichimura Kenichi Imaeda Hiroo Inokuchi 《Molecular Crystals and Liquid Crystals》2013,570(1):649-654
Abstract Rare gases such as He, Ne and Ar are trapped in the lattice of solid C60 and (NaH)4C60 under conditions of ambient temperature and pressure. The mass analyzed thermal desorption reveals that rare gases are desorbed above 400K and their desorption amounts are in nonstoichiometric level. Ar2p and Ar3s X-ray photoelectron spectra show large chemical shifts. These results suggest that He, Ne and Ar have charge and are in valence state. 相似文献
5.
Shugo Suzuki Shinìchi Higai Nobutada Nagai Kenji Nakao 《Molecular Crystals and Liquid Crystals》2013,570(1):587-592
Abstract We have studied theoretically the electronic structures of a hypothetical donor-type material, (PH4)3C60, and a hypothetical acceptor-type material, (ClO4)3C60 from first principles by using a full-potential linear-combination-of-atomic-orbitals method based on the density-functional theory within the local-density approximation. It is found that the charge transfer from the PH4 molecules to the C60 molecules is perfect while the charge transfer from the ClO4 molecules to the C60 molecules is not perfect. We compare the latter result with the electronic structures of two typical acceptor-type organic conductors, (TMTSF)2ClO4 and (TMTSF)2PF6, and discuss the differences. 相似文献
6.
H. Ootoshi K. Ishii A. Fujiwara T. Watanuki Y. Matsuoka H. Suematsu 《Molecular Crystals and Liquid Crystals》2013,570(1):565-570
Abstract We have studied crystal structures of europium C60 compounds by high resolution x-ray diffraction measurements. In the systematic synthesis of Eu x C60 for x (0 ≤ x ≤ 6), two stable phases appear at x = 3 and 6. Eu6C60 has a bcc structure, which is an isostructure to M 6C60 (M represents an alkali or alkaline earth metal). Eu3C60 has a superstructure derived by doubling the fcc pristine C60 crystal along three principal axes. This superstructure comes from an ordering of cation vacancies, which is analogous to Yb2.75C60. 相似文献
7.
利用基于Green's function的tight-binding方法,对由两条原子线电极连接C60分子远端构成的电子传导系统进行了理论计算和数值模拟,得出了入射电子通过C60分子传输到远端点的电子传输谱.其结果揭示了电子传导过程中C60分子的开关特性,并且得出了电子传输能量与分子轨道共振时传输概率峰值的出现及振荡特征.利用Fisher-Lee关系式和量子流密度理论,在传输概率峰值的能量点E=-1.38eV处获得了C60分子内的量子流分布,给出了键量子流的最大值和最小值.对全部分子键上的量子流数值进行了图形模拟,其结果符合量子流动量守恒定律. 相似文献
8.
Silvia Luzzati Fabio Speroni Anvar Zakhidov Shigenori Morita Katsumi Yoshino 《Molecular Crystals and Liquid Crystals》2013,570(1):927-932
Abstract We report the IR spectra and the photoinduced absorption of polyhexylthiophene(PHT) doped with C60. The presence of C60 ?n anions is observed in the IR spectra by a mode at 1383 cm?1 and a broad electronic transition at 1.2 eV, while most of the C60 molecules stay neutral. This is indicative that for a small fraction of C60 molecules, charge transfer occurs in the ground state. The photoinduced absorption spectra display a sharp transition at 1.15 eV peculiar to C60 monoanion, the spectral features change with fullerene concentration. The intensity of the polymer photoinduced bands increases 5-10 times due to photoinduced charge transfer to C60. 相似文献
9.
Hideki Tanaka Jun Onoe Toshiki Kara Aiko Nakao Kazuo Takeuchi 《Molecular Crystals and Liquid Crystals》2013,570(1):701-705
Abstract The interaction between C60 and Si atoms was investigated using X-ray photoelectron spec-troscopy (XPS) for the photo-irradiated Si-deposited C60 film in order to establish a method of a synthesis for the Si-coated C60. It was found that the Cls spectrum of the photo-irradiated film contains a peak due to C-Si bonding, while no peak due to C-Si bonding was observed for the film before photo-irradiation. This indicates that Si atoms stick to C60 when using the present method. 相似文献
10.
《Journal of Non》2006,352(23-25):2488-2491
Charge transfer (CT) and subsequent exciton dissociation are essential for organic donor/acceptor solar cells. We analyze these processes by calculating optical intrachain and CT excitations in a model donor/acceptor system. It is found that the increased electron affinity of low-gap polymers may seriously inhibit the CT efficiency. The consequences for exciton dissociation via tunneling are computed. 相似文献
11.
In this paper, C60 nanocrystals thin film with monocrystal thickness was prepared using a liquid-liquid interface. C60 nanocrystals dispersion prepared by reprecipitation method was added to n-hexane/water interface to form a thin film. The film was transferred onto an ITO substrate. Surface morphology of the film was studied by scanning electron microscope (SEM) and atomic force microscope (AFM) measurements. It was found that the density of the film increase with increasing the deposition number of layers with maintaining the monocrystal thickness. 相似文献
12.
掺杂C60薄膜的制备及光电特性 总被引:1,自引:0,他引:1
在电弧法制备的过程中添加氮气或B2O3粉末,制备了氮、硼替位式掺杂C60.硼掺杂和氮掺杂C60均显示明显的半导体导电特性,且室温电导率比未掺杂C60薄膜提高1~2个量级.用共蒸发的方法制备出了硫掺杂C60薄膜,其电导率~温度曲线中存在一个过渡区,过渡区两侧表现出明显的半导体导电特性,这与掺入C60薄膜中的硫杂质的存在状态有关.其室温电导率比掺杂前提高4个量级,光致发光也明显增强.另外还报道了用离子注入和射频等离子体辅助真空沉积的方法制备掺杂C60薄膜的初步结果. 相似文献
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14.
A. A. Khokhryakov O. A. Kyzyma L. A. Bulavin A. Len M. V. Avdeev V. L. Aksenov 《Crystallography Reports》2007,52(3):487-491
Despite the inability of fullerenes to be directly dissolved in water, there are methods for preparing stable dispersions of fullerenes in water without any particular modifications of the fullerene or addition of stabilizers. The colloidal properties of such systems prepared by replacing the solvent and structural changes in them during coagulation have been studied. The coagulation dynamics has been investigated by spectroscopy and small-angle neutron scattering. The results obtained confirm the colloidal nature of such systems. During coagulation, particles retain a large volume of water around them, an indication of interaction between fullerene and water during solution stabilization. 相似文献
15.
Nobuyuki Kobayashi Shoji Nitta Hitoe Habuchi Takuya Yasui Takashi Itoh Shuichi Nonomura 《Molecular Crystals and Liquid Crystals》2013,570(1):781-786
Abstract C60 molecules were embedded in the pores of a zeolite FSM-16 by using a liquid phase method. The shift of photoluminescence spectra of C60 solid embedded in FSM-16 was discussed using data of ESR, PDS and SAXS. 相似文献
16.
A series of fullerenes from C20 to C60 (a total of 5770) is obtained and their characterization in terms of symmetry point groups is performed for the first time. The most symmetric forms with the sixth and higher orders of automorphism groups (a total of 80) are represented in the Schlegel projection onto one of the faces. It is noted that, among the 5770 fullerenes obtained, only 12 fullerenes exhibit noncrystallographic symmetry. 相似文献
17.
Crystallography Reports - Spectral properties of organic semiconductors (zinc phthalocyanine (ZnPc), fullerene C70, and their mixture (ZnPc : C70) have been studied. The... 相似文献
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19.
M. Ramm P. Luger D. Zobel W. Duczek J. C. A. Boeyens 《Crystal Research and Technology》1996,31(1):43-53
C60 · 2C8H10 (100 K): hexagonal space group P63, a = 23.694(4), c = 10.046(2) Å, V = 4884(2) Å3, Dx = 1.903 g cm−3, Z = 6, F(000) = 2856, γ(CuKa) = 1.54178 Å, μ = 0.84 mm−1. C60 · 2C8H10 (20 K): hexagonal space group P63, a = 23.67(1), c = 10.02(1) Å, V = 4862(6) Å3, Dx = 1.912 g cm−3, Z = 6, F(000) = 2856, γ(CuKa) = 1.54178 Å, μ = 0.84 mm−1. The structures were determined by Patterson syntheses and rigid-body refinements. The C60 molecules show two orientations with one molecular centre in common. The solvent molecules are disordered too. Static disorder could not be overcome or influenced by cooling down. A coordination number of 10 was found for the fullerene molecules. 相似文献
20.
Toshiki Hara Jun Onoe Hideki Tanaka Kazuo Takeuchi 《Molecular Crystals and Liquid Crystals》2013,570(1):695-700
Abstract The structural modification induced by electron-beam (EB) in a C60 film and its kinetics have been studied using in situ high-resolution FT-IR spectroscopy. Similar to studies on photoirradiated KxC60 fim, was found that a coalescence reaction between adjacent C60 molecules takes place. In order to investigate the interaction between an incident electron and Cgg molecules, the time-dependence of the amounts of C60 on the EB irradiation was examined. It was found that the reaction rate exhibits a linear dependence on the reactant concentration and nonlinear dependence on the incident current. 相似文献