Theoretical Study of Potential Energy Surfaces for N₁₂ Clusters

Two new isomers of N12 clusters were reported in addition to the four isomers previously studied. The decomposition pathways of these six N12 isomers were studied by using the density functional theory (DFT) method at the B3LYP/6-31G* level. Relative energies were further calculated at the B3LYP/6-311+G(3df, 2p)//B3LYP/6-31G* level. DFT predicts that the dissociation of diazobispentazole proceeds via ring breaking and the barrier height is only 4.0 kcal/mol at the B3LYP/6-311+G(3df,2p)//B3LYP/6-31G* level. The dissociation reaction of N12 consisting of an aromatic N5 ring and a N7 open chain prefers ring breaking, at a cost of 9.2 kcal/mol, to breaking a bond in the side chain. For open-chain N12 (C2h) isomer, the B3LYP/6-311+G(3df,2p)//B3LYP/6-31G* barrier height for the N2 elimination reaction is 14.5 kcal/mol. As for the cyclic and cagelike isomers, their decomposition barrier heights are all much lower than 10 kcal/mol. From the results presented here, it seems that these six isomers are not kinetical...