The electronic structure of the ternary intercalated graphite β-KS0.25C3 is studied by means of a first-principles density functional theory approach. The nature of the partially filled bands is analyzed, and the K sublayers of the intercalate are shown to have an important contribution to the Fermi surface. This K-based contribution confers a sizable three-dimensional character to the conductivity even if considerably less than that for the related binary KC8. The electronic structure of β-KS0.25C3 differs noticeably from that of the related ternary compound, KHxC4. The charge transfer is analyzed, and a way to evaluate it, which can be used in general for intercalated graphites, is proposed. The charge transfer per C atom in this ternary material is shown to be smaller than that in the KC8 binary compound despite a more favorable stoichiometry ratio between K and C. © 2006 American Chemical Society.
|Publication status||Published - 13 Nov 2006|