Enhanced electric polarizability in metal C60 compounds:: Formation of a sodium droplet on C60

We measured the electric polarizability of NaNC60 (N=1-34) molecules. The experimental values can be interpreted by the existence of a permanent electric dipole for every size. This cannot be explained by a metal shell around the C-60, but this is in agreement with a sodium cluster bound to the C-60. (C) 2001 American Institute of Physics.