hydrogenation. Too much energy will lead to the destruction of the molecule. The spatial angle for hit should be around $90^{\circ}, \pm 10^{\circ}$, but this parameter was not investigated in detail, and may also vary. Possible candidate particles can be found in different environments like stellar winds, AGB stars and winds or PNe. The probability for a collision in such environments can be estimated as follows: Using energy conservation and momentum conservation and taking the parameters of a typical C-rich AGB stellar wind, the collision probability can be calculated. Even these very simplified calculations show a few hits per second for a simple stellar wind up to a distance of about 20 R$_\odot$. Recent observations showed evidence of mixed chemistry with emission from both silicate dust and PAHs (Guzman-Ramirez et al. [@liz1]) or the simultaneous presence of mid-IR features attributed to neutral fullerene molecules (i.e. $C_{60}$) and PAHs (García-Hernández et al. [@garcia]). A very recent study discussed that PAHs are located and even formed at the outer edge of dense tori (Guzman-Ramirez et al. [@liz2]). The presence of a dense torus has been strongly associated with the rich and mixed chemistry seen in these regions. All these observed environments strongly 