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Electrochemical reduction of cationic Li+@C60 to neutral Li+@C60?-: isolation and characterisation of endohedral [60]fulleride.

ABSTRACT: Lithium-encapsulated [60]fullerene Li@C60, namely, lithium-ion-encapsulated [60]fullerene radical anion Li+@C60?-, was synthesised by electrochemical reduction of lithium-ion-encapsulated [60]fullerene trifluoromethanesulfonylimide salt [Li+@C60](TFSI-). The product was fully characterised by UV-vis-NIR absorption and ESR spectroscopy as well as single-crystal X-ray analysis for the co-crystal with nickel octaethylporphyrin. In solution Li@C60 exists as a monomer form dominantly, while in the crystal state it forms a dimer (Li@C60-Li@C60) through coupling of the C60 radical anion cage. These structural features were supported by DFT calculations at the M06-2X/6-31G(d) level of theory.

SUBMITTER: Ueno H

PROVIDER: S-EPMC6022080 | biostudies-other | 2016 Sep

REPOSITORIES: biostudies-other

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Electrochemical reduction of cationic Li+@C60 to neutral Li+@C60˙-: isolation and characterisation of endohedral [60]fulleride.

Ueno Hiroshi H Aoyagi Shinobu S Yamazaki Yu Y Ohkubo Kei K Ikuma Naohiko N Okada Hiroshi H Kato Tatsuhisa T Matsuo Yutaka Y Fukuzumi Shunichi S Kokubo Ken K

Chemical science 20160620 9

Lithium-encapsulated [60]fullerene Li@C60, namely, lithium-ion-encapsulated [60]fullerene radical anion Li+@C60˙-, was synthesised by electrochemical reduction of lithium-ion-encapsulated [60]fullerene trifluoromethanesulfonylimide salt [Li+@C60](TFSI-). The product was fully characterised by UV-vis-NIR absorption and ESR spectroscopy as well as single-crystal X-ray analysis for the co-crystal with nickel octaethylporph ...[more]

PMID: 30034715

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