Averaged anharmonic IR spectra of cata- and peri-condensed PAHs. For cata-condensed PAHs, averages are taken over one to six ring systems for cationic (C) and anionic (A) states and one to five ring systems for the neutral (N) state, while peri-condensed PAHs include one to six ring systems for all charge states (C, N, A). Three spectral regions are shown: (a) C–H stretching (3.0–3.4 μm), (b) C–C stretching and C–H in-plane bending (6.0–9.0 μm), and (c) C–H out-of-plane bending (11.0–13.0 μm). Observational data are obtained from JWST (https://irsa.ipac.caltech.edu/data/ISO/SWS/) and are baseline corrected, emission line suppressed, and normalized to improve dynamic range and enable direct comparison. Dotted vertical lines indicate the observed positions of AIBs.