PAH emission spectra at different points inside the NW PDR of NGC 7023. For each species, the spectra have been derived by adding the contributions of all ionization and hydrogenation states, from the abundances presented in Appendix D. The results for C₂₄H₁₂ derivatives are shown in black, while the spectra for C₅₄H₁₈ and C₉₆H₂₄ species are shown in blue and red, respectively. The spectra have been conveniently normalized to the peak intensity of the 6.7 μm band for C₂₄H₁₂ derivatives, and to the 11.2 μm band for the larger species.