Photodissociation roaming atom mechanism

However, as the CH3 + O reaction shows [67], the roaming atom mechanism is not limited to closed-shell adducts, nor is it limited to abstraction pathways that are barrierless (see Fig. 13). Finally, the photodissociation of CH3CHO implies that the roaming fragment may not be limited to H atoms [55]. It remains to be seen how universal roaming mechanisms are, but they have the potential to be competing pathways in a large number of reactions. 

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