Theoretical scaled IR spectra of PAH-C₆₀ bis-adducts from 2H-indene (2InC₆₀, a–c) and indenyl (2IylC₆₀, d and e). The dashed red spectra correspond to the mono-adduct analogues, while the dashed blue lines mark the four strongest C₆₀ features (~7.0, 8.5, 17.4, and 18.9 μm). Note that the convolution parameters are the same as in Figure 4. For a detailed discussion on the models and spectral features we refer to Appendix B.