Influence of charged and excited states on the mechanisms of hexamethylene triperoxide diamine decomposition

摘要

The electronic structures of individual hexamethylene triperoxide diamine (HMTD) molecules in different initial states were calculated with the use of the method of density functional theory (B3LYP/6-31+G(d)). The rupture of one of its three week oxygen-oxygen bonds was considered as the primary mechanism of molecule decomposition. Several initial states of the molecule were examined: the ground state, positively and negatively charged states, the lowest triplet state. The last of the mentioned states was unstable; the rupture of the bond and subsequent restructuring of the molecule took place immediately, in the process of an optimization calculation. The other states of the molecules were stable, but the bond rupture had an exothermal character in all cases. The appropriate transition states characterizing the values of energetic barriers for bond rupture were determined. The height of the barrier was successively reduced at transferring from the ground state to the positively and negatively charged states of the molecule. Results on the influence of charged and excited states on the mechanisms of decomposition of dimethyl peroxide molecules were obtained too. These results had a certain similarity to the results obtained for HMTD, but the highest energetic barrier for the oxygen bond rupture was observed here in the positively charged state.