Abstract

The decomposition mechanism of the pentanitrogen (N₅, N₅⁻, N₅⁺) and hexanitrogen (N₆, N₆⁺, N₆⁻) clusters and their ions was studied using ab initio MO calculations up to the CCSD(T) level with 6-311+G(3dp) and aug-cc-pVTZ basis sets and also DFT/B3LYP method. While the cyclic anion N₅⁻ and open-chain cation N₅⁺ are relatively stable with respect to elimination of N₂, the neutral N₅ radical does not exist as a discrete species. The elimination of two N₂ molecules in the neutral N₆ is found to be a concerted process, whereas that in the ionized N₆⁺ cluster is stepwise due to the existence of a N₄⁺ ion. The fragmentation of a N₆ cluster into two azide (N₃) fragments is, irrespective of its charge state, also a facile process, making them, at most, metastable molecules. Different thermochemical parameters of these N_n species have also been evaluated.

Article Outline

1. Introduction

2. Details of calculations

3. Results and discussion

3.1. The N₅ radical

3.2. The N₅⁽⁻⁾ anion

3.3. The N₅⁽⁺⁾ cation

3.4. The N₆ molecule

3.5. The N₆^(·+) radical cation

3.6. The N₆^·− radical anion

4. Summary

Acknowledgements

References