title: Li4C60: a polymeric fulleride with a two-dimensional architecture and mixed interfullerene bonding motifs.
abstract: All known fullerene polymers have interfullerene connections via either [2 + 2] cycloaddition or single C-C bonds. The high-resolution synchrotron X-ray powder diffraction technique was employed here to determine the crystal structure of the Li4C60 fulleride. We find that the ground state of Li4C60 is a two-dimensional polymer with monoclinic crystal symmetry and an unprecedented architecture, combining both the [2 + 2] cycloaddition and the single C-C bridging motifs. The small size of the Li+ cations is crucial in stabilizing the resulting tightly packed polymeric structure.
authors.affiliation: Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK. serena.margadonna@ed.ac.uk
authors.forename: Serena
authors.initials: S
authors.lastname: Margadonna
authors.forename: Daniele
authors.initials: D
authors.lastname: Pontiroli
authors.forename: Matteo
authors.initials: M
authors.lastname: Belli
authors.forename: Toni
authors.initials: T
authors.lastname: Shiroka
authors.forename: Mauro
authors.initials: M
authors.lastname: Ricco
authors.forename: Michela
authors.initials: M
authors.lastname: Brunelli