Electronic Structure Studies of Undoped and n -Type Doped Fullerene C 60

Abstract
The electronic structure of undoped and K-doped C60 has been investigated by high-energy electron energy-loss spectroscopy in transmission. Information on the filling and energetic position of π*-levels as a function of dopant concentration is obtained. From momentum-dependent measurements it is concluded that for undoped and doped C60 the π-bands are narrow indicating a weak interaction between the C60 molecules.