  The electronic structure of potassium intercalated picene and coronene films
has been studied using photoemission spectroscopy. Picene has additionally been
intercalated using sodium. Upon alkali metal addition core level as well as
valence band photoemission data signal a filling of previously unoccupied
states of the two molecular materials due to charge transfer from potassium. In
contrast to the observation of superconductivity in K_xpicene and K_xcoronene
(x ~ 3), none of the films studied shows emission from the Fermi level, i.e. we
find no indication for a metallic ground state. Several reasons for this
observation are discussed.
