Fig. 1: Examples of reaction pathways when a PAH molecule (here a coronene cation) is damaged by the knockout of a C atom in a collision with an energetic particle.

These types of reactions are proposed to take place in the ISM where PAH molecules/ions are abundant. The calculated C₂₃H\({}_{x}^{+}\) structures are from Stockett et al.²⁶. Background image credit: ESO/U. G. Jørgensen.