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High Blocking Temperature of Magnetization and Giant Coercivity in the Azafullerene Tb2 @C79 N with a Single-Electron Terbium-Terbium Bond.

ABSTRACT: The azafullerene Tb2 @C79 N is found to be a single-molecule magnet with a high 100-s blocking temperature of magnetization of 24?K and large coercivity. Tb magnetic moments with an easy-axis single-ion magnetic anisotropy are strongly coupled by the unpaired spin of the single-electron Tb-Tb bond. Relaxation of magnetization in Tb2 @C79 N below 15?K proceeds via quantum tunneling of magnetization with the characteristic time ?QTM =16?462±1230?s. At higher temperature, relaxation follows the Orbach mechanism with a barrier of 757±4?K, corresponding to the excited states, in which one of the Tb spins is flipped.

SUBMITTER: Velkos G

PROVIDER: S-EPMC6519270 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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High Blocking Temperature of Magnetization and Giant Coercivity in the Azafullerene Tb2 @C79 N with a Single-Electron Terbium-Terbium Bond.

Velkos Georgios G Krylov Denis S DS Kirkpatrick Kyle K Spree Lukas L Dubrovin Vasilii V Büchner Bernd B Avdoshenko Stanislav M SM Bezmelnitsyn Valeriy V Davis Sean S Faust Paul P Duchamp James J Dorn Harry C HC Popov Alexey A AA

Angewandte Chemie (International ed. in English) 20190327 18

The azafullerene Tb2 @C79 N is found to be a single-molecule magnet with a high 100-s blocking temperature of magnetization of 24 K and large coercivity. Tb magnetic moments with an easy-axis single-ion magnetic anisotropy are strongly coupled by the unpaired spin of the single-electron Tb-Tb bond. Relaxation of magnetization in Tb2 @C79 N below 15 K proceeds via quantum tunneling of magnetization with the characteristic time τQTM =16 462±12 ...[more]

PMID: 30786125

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