Structures and stability of N13+ and N13- clusters

The structures and stabilities of eleven N13+ and N13- isomers have been investigated with second-order Moller-Plesset (MP2) and density functional theory (DFT) methods. Five N13+ isomers and six N13- isomers are all reasonable local minima on their potential energy hypersurfaces. The most stable N13+ cation is structure C-2 with C2v symmetry, which contains a pentazole ring and two N4 open chains. It is different from those of the N7+ and N9+ clusters, but similar to the N11+ cluster. Meanwhile, the most stable N13- structure A-2 is composed of a pentazole ring and a six-membered ring connected by two nitrogen atoms. It is not only different from those of the N7- and N9- clusters, but also from the N11- cluster. The decomposition pathways of structures C-2 and A-2 were investigated at the B3LYP/(aug)-cc-pVDZ level. From the barrier heights of the structures C-2 and A-2 decomposition processes, it is suggested that C-2 is difficult to observe experimentally and A-2 may be observed as a short-lived species.