D.A. Neumann, J.R.D. Copley, R.L. Cappelletti, W.A. Kamitakahara, et al., "Coherent quasielastic neutron scattering study of the rotational dynamics of C60 in the orientationally disordered phase," Physical Review Letters, 67:3808, 1991.
Dan Neumann (National Institute of Standards and Technology, Gaithersburg, Md.): "One of the most compelling features of the molecule C60 is its beautiful symmetric structure. On first reflection, however, there is an apparent paradox, since the molecular shape, that of a truncated icosahedron, contains five- fold symmetry axes that cannot be ideally accommodated within a crystal structure. X-ray and neutron powder diffraction measurements, nevertheless, show that at room temperature solid C60 adopts a face-centered cubic structure.
"NMR results (C.S. Yannoni, et al., Journal of Physical Chemistry, 95:9, 1991; and R. Tycko, et al., J. Phys. Chem., 95:518, 1991) suggested the resolution of this difficulty by demonstrating that dynamic disorder in the orientations of the molecules exists at room temperature. ...
