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Updated: May 30, 2025
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Preparation of Carbon Nanosheets at Room Temperature
Published on: March 8, 2016
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Negative linear compressibility and structural stability of the energetic material trans-hexanitrostilbene under
Xinglong Deng1, Dong Li2, Boyang Fu1
1School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu 611731, Sichuan, China. wzhcai@uestc.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|January 27, 2025
Summary
High pressure causes unusual expansion in energetic 2,2
Area of Science:
- Materials Science
- Crystallography
- Energetic Materials
Background:
- Structural stability of energetic materials like 2,2',4,4',6,6'-hexanitrostilbene (trans-HNS) is crucial for performance and safety.
- Limited research exists on the high-pressure structural behavior of trans-HNS.
Purpose of the Study:
- To investigate the structural response of trans-HNS to external pressure.
- To understand the relationship between molecular reorientation and compressibility.
Main Methods:
- High-pressure single-crystal X-ray diffraction.
- Raman spectroscopy.
Main Results:
- Observed negative linear compressibility (NLC) along the c axis (-4.4(5) TPa⁻¹) up to ~2.90 GPa, attributed to molecular reorientation.
- NLC transitioned to positive linear compressibility (PLC) at higher pressures due to lattice constraints.
- Band gap decreased by ~8.8% up to 10.01 GPa; irreversible changes occurred above 10 GPa.
Conclusions:
- Molecular reorientation drives NLC in trans-HNS under pressure.
- NLC may be a common phenomenon in similar herringbone-structured energetic crystals.
- Irreversible structural changes suggest potential chemical reactions or amorphization at extreme pressures.
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