Layer Structure of Doped C_(60)

It is found in this letter that the doped C_(60) possesses layer-structure in both bond distortions and electronic states.There are eight layers of carbon atoms in the charged C_(60),and its symmetry is reduced from Ih to D_(5d).This layer-structure indicates that there exist four nonequivalent groups of carbon atoms in the doped C_(60).It contrasts with the pristine C_(60),in which all the sixty carbon atoms are equivalent.One observable consequence of such layer-structure is the split of its NMR spectrum with the ratio 1:1:2:2.