▎ 摘　　要

We explore the edge-state-induced exciton effects in graphene nanoflakes with various edges and shapes. The energy degeneracy of the three triplet excitons is preserved in hexagonal armchair-edged graphene nanoflakes and triangle armchair-edged graphene nanoflakes. However, this energy degeneracy is partly broken in hexagonal zigzag-edged graphene nanoflakes, because of the zigzag-edge-induced spin polarization and the antiferromagnetic coupling between nearest-neighboring edges. And the degeneracy is totally broken in triangle zigzag-edged graphene nanoflakes, due to the spin-polarized edge states and the ferromagnetic coupling between nearest neighboring edges in these systems. Published by AIP Publishing.