(Invited) Dynamics of Fullerenes Visualized with Variable Temperature Single-Crystal X-Ray Diffraction

Abstract

The dynamics of fullerenes are fundamentally interesting. Variable temperature single-crystal X-ray diffraction is a powerful tool to view the temperature-driven dynamics of fullerene molecules in the crystal lattice because fullerene crystals present fruitful dynamics information in the widely accessible liquid nitrogen cryostats temperature range (90 K - room temperature). Recently, we succeeded in the visualization of the temperature-driven circular movement of Dy2 inside a benzyl-functionalized C80 cage in its solvate crystal.1 The temperature-driven dynamics of typical fullerene/nickel octaethylporphyrin (NiOEP) co-crystals presented the rather static behaviour of porphyrin molecules, and strong libration of the fullerene cages (C60 and C80) in the temperature range of 100-280 K. While the M3N clusters (M3N = Ho2LuN, Lu3N or Sc3N) inside C80 cage show intriguing temperature-driven dynamics with subtle metal atom size/mass effects.2-3 Sc3N@C70 rotation in the co-crystal with NiOEP induced a phase transition which was visualized with variable temperature single-crystal X-ray diffraction.4 In this contribution, the details of the recently observed temperature-dependent dynamics of fullerene molecules in the crystal lattice will be discussed. Liu, F.; Velkos, G.; Krylov, D. S.; Spree, L.; Zalibera, M.; Ray, R.; Samoylova, N. A.; Chen, C.-H.; Rosenkranz, M.; Schiemenz, S.; Ziegs, F.; Nenkov, K.; Kostanyan, A.; Greber, T.; Wolter, A. U. B.; Richter, M.; Büchner, B.; Avdoshenko, S. M.; Popov, A. A., Air-stable redox-active nanomagnets with lanthanide spins radical-bridged by a metal–metal bond. Nat. Commun. 2019, 10, 571.Liu, F.; Spree, L., Molecular Spinning Top: Visualizing the Dynamics of M3N@C80 with Variable Temperature Single Crystal X-ray Diffraction. Chem. Commun. 2019, 55, 13000-13003.Hao, Y.; Wang, Y.; Spree, L.; Liu, F., Rotation of fullerene molecules in the crystal lattice of fullerene/porphyrin: C60 and Sc3N@C80. Inorg. Chem. Front. 2021, 8, 122-126.Hao, Y.; Wang, Y.; Dubrovin, V.; Avdoshenko, S. M.; Popov, A. A.; Liu, F., Caught in Phase Transition: Snapshot of the Metallofullerene Sc3N@C70 Rotation in the Crystal. J. Am. Chem. Soc. 2021, 143, 612-616.