Crystal Structures and Sensitivity Properties of the Energetic Coordination Compounds Based on Ligands with High Nitrogen Content

Jian-Guo Zhang, State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing, China (zjgbit@bit.edu.cn)
Junqing Yang, State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing, China
Tong-Lai Zhang, State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing, China
Michael Gozin, School of Chemistry, Faculty of Exact Science, Tel Aviv University, Tel Aviv, Israel

Certain metal coordination compounds have properties of energetic materials, possessing stable structures, high detonation performance and low sensitivity to mechanical stimuli. Due to these properties, many of the energetic metal coordination compounds have a potential to be used in a broad range of civil and defense applications, as primary explosives, combustion catalysts and pyrotechnics.

In this work, crystal structures, detonation properties and sensitivity to mechanical impact and friction of a series of energetic metal coordination compounds, based on carbohydrazide (CHZ), 3-hydrazino-4-amino-1,2,4-triazole (HATr), 1,5-diaminotetrazole (DAT) the nitrogen-rich ligands were studied. These ligands show different coordination characteristics and diversity, which were found to be dependent on the nature of the coordinated metal ion and on properties of incorporated anions. The CHZ ligand typically coordinated metal cation in a chelating bidentate mode or in a bridging tridentate mode, forming stable coordinated polyhedrons. The HATr ligand was also found adopting similar types of coordination behavior, exhibiting formation of a range of mononuclear, binuclear and trinuclear complexes, as a function of the coordinated metal cation. Some of the HATr-containing complexes were found to be coordination polymers, with zigzag-shaped chain arrangement in their crystals. In contrast, despite its structure, the DAT ligand was found to function as a monodentate ligand, which was usually bound to the metal centers via its 4-N atom of the tetrazole ring.

We found that the type of a metal center, the mode of coordination and the coordination structure have clear and direct effect on the detonation and sensitivity properties of the resulted energetic nitrogen-rich coordination compounds, allowing significant flexibility in the molecular and crystal design, as well as prediction of desired properties for these energetic materials.

Keywords

Energetic coordination compounds; nitrogen-rich ligands; crystal structures; sensitivity.

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Short Biography of Presenting Author

Jian-Guo Zhang received his Ph. D. in Applied Chemistry at the Beijing Institute of Technology. He was appointed as a Faculty Fellow in the School of Mechatronical Engineering at the Beijing Institute of Technology since 2000. He has served as a Vice Dean at the School of Mechatronical Engineering. In 2012, he was named a University Distinguished Young Professor. His research interests include the molecular design, syntheses, characterization, properties, and application of energetic materials, and hydrogen storage materials. He currently serves on the Editorial Board of Central European Journal of Energetic Materials, Defense Technology, and Chinese Journal of Energetic Materials journals. He has published more than 300 publications and is author of more than 50 patents and patent applications.