  In this work, we report for the first time the crucial role of topological
anomalies like Stone-Wales (SW) type bond rotations in tuning the optical
properties of graphene quantum dots (GQDs). By means of first-principles
calculations, we first show that the structural stability of GQDs strongly
depends on position of SW defects. Optical absorption spectra is then computed
using electron-correlated methodology to demonstrate that SW type
reconstruction is responsible for the appearance of new defect-induced peaks
below the optical gap and dramatically modifies the optical absorption profile.
In addition, our investigations signify that electron correlation effects
become more dominant for SW-defected GQDs. We finally establish that the
introduction of SW defects at specific locations strongly enhances light
absorption in visible range, which is of prime importance for designing light
harvesting, photocatalytic and optoelectronic devices.
