Graphite energy bands

Molodtsov, S. L., Th. Gantz, C. Laubschat, A. G. Viatkine, J. Avila, C. Cassdo, and M. C. Asensio. 1996. Electron-energy bands in single-crystalline La-intercalated graphite. Z. Phys. B 100 381-385. 

Active carbon is a composite of amorphous and microcrystalline substructures and exhibits semiconducting properties. An interpretation of the mechanism of electronic conduction in active carbon is more complicated than that for crystalline (graphitized) carbon. The conduction processes are very different becau.se the current carriers in active carbon are assumed to be localized by disorder, which introduces randomness into the potential-energy bands for electrons. 

Schematic diagram of the energy bands and the position of the Fermi level for the aromatic solids starting from molecular solids (a) and ending on a perfect graphite crystal (e). The heat-treatment temperature H and the approximate variation of the crystallite diameter d (a-dimension) and energy gap AE are shown...

Each carbon atom in the graphite structure contributes 4 valence electrons, resulting in 16 energy bands, 4 of them Jt-bands (two bonding and two antibonding) on either side of the Fermi level. In AB-stacked graphite, the separation between the... 

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