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Preparation and Reactivity of Gasless Nanostructured Energetic Materials
Published on: April 2, 2015
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Detonation Performance of Insensitive Nitrogen-Rich Nitroenamine Energetic Materials Predicted from First-Principles
Dezhou Guo1, Yuanyuan Wei1, Sergey V Zybin2
1State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
JACS Au
|April 26, 2024
Summary
Researchers explored new energetic materials derived from FOX-7. They found that replacing a nitro group with a tetrazole ring in FOX-7-T reduces detonation performance due to altered decomposition pathways and product formation.
Area of Science:
- Energetic Materials Science
- Computational Chemistry
- Chemical Engineering
Background:
- 1,1-diamino-2,2-dinitroethylene (FOX-7) is a valuable energetic material (EM) due to its balance of high detonation properties and low sensitivity.
- Developing FOX-7 derivatives is desirable, but many exhibit high sensitivity, limiting their practical application.
- 1,1-diamino-2-tetrazole-2-nitroethene (FOX-7-T), a derivative with a tetrazole ring, shows good stability but unexpectedly lower detonation performance than FOX-7.
Purpose of the Study:
- To investigate the atomistic reasons behind the reduced detonation performance and insensitivity of FOX-7-T compared to FOX-7.
- To understand the role of functional groups in the initial decomposition reactions of these energetic materials.
- To provide insights for designing next-generation high-nitrogen energetic materials.
Main Methods:
- Reactive molecular dynamics (RxMD) simulations utilizing the ReaxFF reactive force field.
- Combined quantum mechanics and molecular dynamics (QM-MD) simulations.
- First-principles-based simulations to predict detonation parameters.
Main Results:
- The initial decomposition mechanism differs significantly between FOX-7 and FOX-7-T.
- FOX-7 decomposes via hydrogen transfer, while FOX-7-T undergoes tetrazole ring breaking at lower temperatures, forming N2 and initiating subsequent reactions.
- Simulations predicted FOX-7-T has substantially lower calculated Chapman-Jouguet (CJ) pressure, detonation velocity, and CJ temperature compared to FOX-7.
- Reduced energy delivery in FOX-7-T is attributed to the formation of condensed-phase carbon clusters, hindering the generation of gaseous products like CO2 and N2.
Conclusions:
- The functional group significantly influences the decomposition pathways and energetic performance of FOX-7 derivatives.
- The tetrazole ring in FOX-7-T leads to less efficient energy release compared to the nitro group in FOX-7.
- Oxygen balance is a critical parameter for designing high-nitrogen energetic materials with optimal performance.
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