Molecular Spectroscopic Study of Metallofullerenes

金属富勒烯的分子光谱研究

基本信息

批准号：
11165243
负责人：
KATO Tatsuhisa
金额：
$ 6.98万
依托单位：
Okazaki National Research Institutes
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas (A)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11165243/
关键词：
Metallofullerene Lanthanide metal 4f-electron ESR measurement ENDOR測定 HYSCORE測定

项目摘要

Electron spin resonance (ESR) spectroscopy has been a powerful technique for the characterization endohedral metallofullerenes. Several examples of the ESR measurement for metallofullerenes are introduced in my talk. Besides a conventional cw-ESR technique, a pulsed-ESR technique developed the further investigation for the properties of metallofullerenes.Various metallofullerenes of lanthanide metals were abundantly obtained [1-3]. Among them the electronic structure of Gd atom is described as 4f^75d^16s^2, and the ground high spin state is expected. We examined Gd@C_<82> by means of X- and W-band ESR spectrometers. The spectrum of X-band ESR exhibited a complex pattern corresponding to that for the high-spin system with large fine structure. The un-symmetric spectral feature was given because of the large zero-field splitting parameters D and E, and prevented us from an easy spectral simulation. The W-band ESR measurement was performed to simplify the spectrum of Gd@C_<82>. I present … More the result of the W-band ESR measurement and the discussion of the electronic structure of Gd@C_<82>.A paramagnetic metallofullerene is a nice building block for a molecular magnet. Wrapping of a metallofullerene with larger π-conjugated molecular envelopes is of great interest, which may lead to an extension of the super-molecular magnet in a 3D-fashion. Tashiro et al. have synthesized a cyclic dimmer of metalloporphyrin [4], and reported the big association constant of 6.7 x 10^5 M^<-1> for the inclusion complex of a cyclic dimmer of zinc porphyrin with C_<60> in benzene solution. The electron spin state of an inclusion complex of a cyclic dimmer of metalloporphyrin with metallofullerene was investigated by means of pulsed-ESR measurement. The direct experimental evidence of the coupled spin state of S=3/2 was obtained for the cyclic dimmer of copper-porphyrin with La@C_<82> by the nutation measurement of pulsed-ESR. A big variety would be expected for the spin state of the inclusion complex in terms of the combination of metals on a porphyrin and a fullerene. Less

电子自旋共振 (ESR) 光谱是一种用于表征内嵌金属富勒烯的强大技术，我的演讲中介绍了金属富勒烯 ESR 测量的几个示例，除了传统的连续 ESR 技术之外，脉冲 ESR 技术还进一步研究了该技术。人们已经大量获得了各种镧系金属富勒烯[1-3]，其中Gd的电子结构。原子被描述为 4f^75d^16s^2，并且我们通过 X 和 W 波段 ESR 光谱仪检测了 Gd@C_<82> 的基态高自旋态。由于零场分裂参数 D 和 E 较大，导致了与具有大精细结构的高自旋系统相对应的复杂图案，从而导致了不对称的光谱特征，这使我们无法进行简单的光谱模拟。进行 W 波段 ESR 测量是为了简化 Gd@C_<82> 的光谱。我展示了 W 波段 ESR 测量的结果以及对 Gd@C_<82> 电子结构的讨论。顺磁性金属富勒烯。是分子磁体的一个很好的构建模块，用更大的 π 共轭分子包络包裹金属富勒烯引起了人们的极大兴趣，这可能会导致超分子磁体的延伸。 3D-fashion 等人合成了金属卟啉的环状二聚体 [4]，并报道了锌卟啉环状二聚体与 C_ 的包合物的大缔合常数为 6.7 x 10^5 M^<-1>。 <60>在苯溶液中通过以下方法研究了金属卟啉的环状二聚体与金属富勒烯的包合物的电子自旋状态。通过脉冲ESR测量，获得了铜卟啉与La@C_<82>的环状二聚体耦合自旋态的直接实验证据。就卟啉和富勒烯上的金属组合而言，包合物的自旋状态预计较小。