4 th ) On the other hand, the zigzag-end-localized HOMO-LUMO gaps of the open-shell singlet or the triplet states provide a very good estimate of the "mixed" ΔΕzz gap. 5 th ) Further refinement of all these three gaps ("bulk", "surface") can be obtained, if needed, by the analysis of the orbital composition of the main peaks of the excitation spectrum obtained by TDDFT. This can also help the correct identification (and nature) of the gaps.