The above observation can be elucidated only by monitoring the participating atoms for each mode, the valuable result of this present work. Despite small number of atoms participating in the chosen reaction, the distinction of atoms into clearly separated groups is possible, with regard to their participation in the reaction events, as understood with chemical intuition: (i) the mobile atom H4, (ii) the affected atoms N1, H5, O3, and (iii) the spectator atoms C2, H6.