Li 4 C 60, one of the best representatives of lithium intercalated fullerides, features an unusual type of two-dimensional polymerization. Extensive investigations, including laboratory x-ray and synchrotron radiation diffraction, C 13 NMR, magic angle spinning, and Raman spectroscopy, show a monoclinic I 2∕ m structure, characterized by chains of [2+ 2]-cycloaddicted fullerenes, sideways connected by single C–C bonds. This leads to the formation of polymeric layers, whose insulating nature, deduced from the NMR and Raman spectra, denotes the complete localization of the electrons involved in the covalent bonds.
American Physical Society
27 Oct 2005
Volume: 72 Issue: 15 Pages: 155437
Physical Review B