Vibrational structure of endohedral fullerene Sc3N@C78 (D3h'): evidence for a strong coupling between the Sc3N cluster and C78 cage
Matthias Krause1, Alexey Popov, Lothar Dunsch
1Group of Electrochemistry and Conducting Polymers, Leibniz-Institute for Solid State and Materials Research Dresden, 01171 Dresden, Germany. matthias.krause@chemie.tu-dresden.de
Abstract:
The vibrational structure of the endohedral cluster fullerene Sc(3)N@C(78) is studied by FTIR spectroscopy, Raman spectroscopy and DFT-based quantum chemical calculations. Remarkably good agreement between experimental and calculated spectra is achieved and a full assignment of the Sc(3)N-based vibrational modes is given. Significant differences in the vibrational structure of the endohedral cluster fullerene Sc(3)N@C(78) and the empty, charged C(78) (6-): 5 (D(3h)') are rationalized by the strong coupling between the Sc(3)N cluster and the fullerene cage. This coupling has its origin in a significant overlap of the Sc(3)N and C(78) molecular orbitals, and causes atomic-charge and bond-length redistributions compared to the neutral C(78) and the C(78) (6-) anion. An ionic model is not sufficient to describe the electronic, geometric and vibrational structure of the Sc(3)N@C(78) nitride cluster fullerene.
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