Electronic energy state of a periodic porous nanoscale graphite

The electronic energy states of periodic porous nanoscale graphites with acene and phenanthrene edge structures are studied with a two-dimensional, tight-binding crystal orbital method in the framework of the Huckel approximation. The electronic energy scheme of the periodic porous graphite is not only determined by the edge shape of the pore in the short-range order from the viewpoint of the calculated unit cell with an acene- or phenanthrene-edge structure, but also by the long-range order from the viewpoint of the graphite plane with an acene- or phenanthrene-edge structure. The appearance of flat bands in periodic porous nanostructured graphite have been theoretically demonstrated.