Structure and Dynamics of Carbon Buckyballs Encapsulated to Single-Walled Carbon Nanotubes

The structural and dynamical attributes of C60 chains inserted inside Single Walled carbon Nanotubes (SWNT) have been investigated by x-ray and neutron refraction, and inelastic neutron scattering (INS). The mensuration have been performed on a large mass of a very high quality carbon peapods sample. We showed that powder refraction could hardly give definitive response on the way the C60s are bonded inside SWNT. However, the comparison of the neutron-derived generalized compression of states (GDOS) of the inserted C60 peas with the GDOS of the same objects derived from lattice dynamics computations led to unambiguous results. The witnessing of excitations in the 8-15 meV span is a clear evidence for the presence strong bonds among C60s in the sample. In the same time, the witnessing of a very weak quasi-elastic signal may be relevant to rotational motions of C60 monomers inside the SWNT. These results suggest that peapods are built of a mixed phase of C60 monomers and C60 n-mers.