Sodium catalytic phenylpentazole cracking: a theoretical study

Abstract

This work presents an in-depth investigation into the cracking reaction mechanism of phenylpentazole (C₆H₅N₅) under the catalytic influence of sodium metal, utilizing density functional theory. The geometries of the reactants, transition states, intermediates, and products are meticulously optimized employing the GGA/PW91/DNP level of theory. Also, a rigorous analysis is undertaken, encompassing various key factors including configuration parameters, Mulliken charges, densities of states, and reaction energies. Three distinct reaction pathways are comprehensively examined, shedding light on the intricate details and intricacies of each pathway. The results show that a remarkable outcome in which the activation energy of the C₆H₅N₅ cracking reaction releases N₂, facilitated by catalytic metal Na, reveals a strikingly reduced value of a mere 5.2 kcal mol⁻¹ compared to the previously reported activation energies ranging from 20 to 30 kcal mol⁻¹. Evidently, this significantly lowered barrier can be readily surpassed at typical room temperatures, exhibiting practical applicability. Notably, the alkali metal Na effectively serves as a catalyst, successfully diminishing the activation energy required for N₂ production through the pyrolysis of pentazole compounds. This breakthrough discovery provides a theoretical basis for experimental research on the low-temperature cracking of pentazole compounds. It also offers valuable insights for the development and application of new high energy density materials, contributing to the creation of a green and low-carbon circular economic system.