Design and selection of pyrazolo[3,4-d][1,2,3]triazole-based high-energy materials

Jin Xinghui,Hu Bingcheng,Zhou Jianhua,Liu Luhao

doi:10.1007/s11224-021-01849-0

Abstract

In this study, we design a series of bridged energetic compounds based on pyrazolo[3,4-d][1,2,3]triazole to screen potential energetic materials with excellent detonation properties and acceptable sensitivities. The electronic structures, heats of formation, detonation velocity, detonation pressure, and impact sensitivity of the designed compounds were calculated using density functional theory. The results showed that the designed compounds have high positive heats of formation in the range of 1035.4 (A7) to 2851.4 kJ mol−1 (D2). Moreover, the designed compounds have high crystal densities and heats of detonation, which significantly enhance detonation pressures and velocities. The detonation pressures and velocities are in the ranges of 6.23 (A1) to 9.65 km s−1 (D3) and 15.7 to 43.9 GPa (E8), respectively. The impact sensitivity data also suggest that the designed compounds have impact sensitivities in an acceptable range. Considering detonation pressures, detonation velocities, and impact sensitivities, six compounds (C3, C5, D3, D5, E3, and F3) were screened as potential materials with high-energy density, excellent detonation properties, and low impact sensitivities. Finally, the electronic structures of the screened compounds were simulated to provide further understanding on the physicochemical properties of these compounds.

Highlights

As a special important component of energy, energetic materials have played an important role in the development of military and its equipments.[1,2,3,4,5,6] In the face of increasing armed conflicts around the world, the leaders of different countries pay significant attention to the development of national armaments and desire higher performance of energetic materials and frequency of replacement
We design a series of bridged energetic compounds based on pyrazolo[3,4-d][1, 2, 3]triazole to screen potential energetic materials with excellent detonation properties and acceptable sensitivities
The results showed that the designed compounds have high positive heats of formation in the range of 1035.4 (A7) to 2851.4 kJ mol−1 (D2)

Summary

Introduction

As a special important component of energy, energetic materials (such as propellant, explosive and initiator) have played an important role in the development of military and its equipments.[1,2,3,4,5,6] In the face of increasing armed conflicts around the world, the leaders of different countries pay significant attention to the development of national armaments and desire higher performance of energetic materials and frequency of replacement. Research on energetic materials is focussed on nitrogen-rich compounds with high energy density, excellent detonation performance, good thermal stability, and reduced amount of polluting gas in the process of explosion.[7,8,9,10,11] Scheme 1 shows the structures of some energetic compounds such as 1,3,5-trinitro-1,3,5-triazinane (RDX),12 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX),[13] and cage structures 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclododecane (CL-20).[14] Among these structures, the detonation performance of cage-like energetic compounds is stronger than that of chain-like energetic compounds. The annular nitrogen-rich energetic compounds combine the benefits of the chain-like and cage-like energetic compounds and lead the field of energetic materials.[15], pyrazolo[3,4-d][1, 2, 3]triazole has good detonation performance and excellent impact sensitivity. By comparing with the RDX and HMX, the energetic compounds with excellent detonation performance and impact sensitivity were screened as reserve materials and for subsequent directional synthesis

Results And Discussion

Heats of formation

Detonation properties

Electronic structures

Conclusion