3. Computational details
The reactions selected were studies using the forward (f ) and reverse (r ) intrinsic reaction coordinate (IRC) path. In each reaction was calculated the transition states. The transitions states were revised in order to present one and only one negative eigenvalue of the energy second derivative matrix and the associated characteristic negative frequency. In the computational protocol was generated several sets of atomic positions correspond to the calculated points on the IRC. The last generated structures on the end of each calculated IRC path were then further geometry optimized to local minimum energy structures. All IRC calculations were developed with mass-weighted coordinates and the reaction path step-size used in all cases was the default value of 0.1 amu1/2-Bohr. Finally, on each point on each IRC path (including the end minima), single-point calculations were generated the necessary density information. All calculation data were carried out using DFT B3LYP/6-311+G(d,p) with the Gaussian 09vD.0149 program. The stability of all calculations generated were checked using the wave functions to perturbations including spin restricted - unrestricted perturbations and were found to be stable. Finally, the QTAIM and stress analysis was performed with the AIMAll 50 suite on the wave function obtained.