From the four possible C -C and C -O bond breakage reactions, both reaction exploration methods report all four. Activation energies as calculated by ReaxFF/CHO2016 are 94.8 kcal mol -1 (R6), 22.2 kcal mol -1 (R1), 36.7 kcal mol -1 (R4), and 165.8 kcal mol -1 (not observed here). The CH 2 dissociation (R6) is quickly found by both methods, although it has a barrier of 94.8 kcal mol -1 . In order to find this reaction, PESmapping just accelerates C -C bond breakage, and CTY-TAD benefits from the low-energy DS, which was reached here on average 46.7 kcal mol -1 below the actual TS (see also Fig. ). The sole O dissociation is not found, because it involves breaking a double bond and thus its activation energy is very high. Moreover, the high activation energy induces a follow-up concerted double beta-scission, which can be seen in R14.