| Project/Area Number |
11165243
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| Research Category |
Grant-in-Aid for Scientific Research on Priority Areas (A)
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| Allocation Type | Single-year Grants |
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| Research Institution | Okazaki National Research Institutes |
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Principal Investigator |
KATO Tatsuhisa Institute for Molecular Science, Okazaki National Research Institute, Professor, 分子科学研究所, 助教授 (80175702)
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| Project Period (FY) |
2000 – 2001
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| Project Status |
Completed (Fiscal Year 2001)
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| Budget Amount *help |
¥10,900,000 (Direct Cost: ¥10,900,000)
Fiscal Year 2000: ¥4,500,000 (Direct Cost: ¥4,500,000)
Fiscal Year 1999: ¥6,400,000 (Direct Cost: ¥6,400,000)
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| Keywords | Metallofullerene / Lanthanide metal / 4f-electron / ESR measurement / ENDOR測定 / HYSCORE測定 |
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| Research Abstract |
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
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