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arXiv · 1801.10258

Crystalline C60 fulleride with metal inside

Ayano Nakagawa·Makiko Nishino·Hiroyuki Niwa·Katsuma Ishino·Zhiyong Wang·Haruka Omachi·Ko Furukawa·Takahisa Yamaguchi·Tatsuhisa Kato·Shunji Bandow·Jeremy Rio·Chris Ewels·Shinobu Aoyagi·Hisanori Shinohara
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Abstract

Endohedral metallofullerenes have been extensively studied, since the first experimental observation of La@C60 in a laser-vaporized supersonic beam in 1985. However, all of these studies have been carried out on metallofullerenes larger than C60 such as (metal)@C82, and there are no reported purified C60-based metallofullerenes except for [Li@C60]+(SbCl6)- salt. Pure (metal)@C60 has not been obtained because of their extremely high chemical reactivity. We report here the first isolation, structural determination and electromagnetic properties of crystalline C60-based metallofullerenes, Gd@C60(CF3)5 and La@C60(CF3)5. Synchrotron X-ray single-crystal diffraction reveals that La and Gd atoms are indeed encapsulated in the Ih-C60 fullerene. The HOMO-LUMO gaps of Gd@C60 and La@C60 are significantly widened by an order of magnitude with addition of CF3- groups. Magnetic measurements show the presense of a weak antiferromagnetic coupling in Gd@C60(CF3)3 crystals at low temperatures. Gd@C60 and La@C60 might exhibit superconductivity as the electronic structures resemble those of superconducting alkali-doped C60 fullerides.

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Ayano Nakagawa, Makiko Nishino, Hiroyuki Niwa, Katsuma Ishino, Zhiyong Wang, Haruka Omachi, Ko Furukawa, Takahisa Yamaguchi, Tatsuhisa Kato, Shunji Bandow, Jeremy Rio, Chris Ewels, Shinobu Aoyagi, Hisanori Shinohara. 2018-01-31. Crystalline C60 fulleride with metal inside. https://arxiv.org/abs/1801.10258

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