Fig. 2: Projected band structures and corresponding DOS showing Van Hove singularities.
From: Spin–valley Hall phenomena driven by Van Hove singularities in blistered graphene

a C2 nonmagnetic case, the red color representing the contribution from the pz orbitals of the blister atoms; b spin-polarized case of C2, the green and red color representing the up and down spin; c, d are for the ground state of C4 and C6, respectively; The size of the circles represents the relative weights of the pz orbitals of the blister atoms.