Figure 2

The band structures of BC ₂ N nanoribbons of the models A (a), B (b), C (c), and D (d) for N = 8. In each panel, the result within DFT is shown in (i) and those within TB model are shown in (ii, iii, iv). Note that the center of the energy, E = 0, does not mean the Fermi level in models C and D within TB model. In (c - iv) and (d - iv), the improved band structures by adding the extra site energies at the outermost atoms are indicated by the blue dotted lines.