Figure 4.

Frontier orbitals of the 25 antidots patterned 12A × 16Z nanographene without external field (a) and with external electric field in the vertical (b) and horizontal (c,d) directions. The results in (d) correspond to a slightly different excited state induced by the field. The numbers below the orbital plots indicate their (orbital) energies (in hy). For the zero-field case, the symmetry of the orbitals is also shown together with the orbital energies. The horizontal lines separate occupied and nonoccupied orbitals.