Time-resolved Raman spectroscopy study of rapid compressed β-HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine)...

Area of Science:

• Materials Science
• Chemical Physics
• High-Pressure Physics

Background:

• β-HMX is a critical energetic material.
• Understanding its structural response under dynamic compression is vital for safety and performance.
• Previous studies primarily used static compression methods.

Purpose of the Study:

• To investigate the high-pressure structural behavior of β-HMX using time-resolved Raman spectroscopy.
• To determine the effect of varying compression rates on phase transitions.
• To assess the reversibility and chemical stability of β-HMX under pressure cycling.

Main Methods:

• Time-resolved Raman spectroscopy.
• Dynamic diamond anvil cell (DAC) for pressures up to 20 GPa.
• Variable compression rates from 0.03 to 1.07 GPa/s.

Main Results:

• Observed phase transitions at ~5.7 GPa (β→ζ) and ~9.5 GPa (ζ→ɛ), consistent with static studies.
• Phase transition pressures were independent of compression rates, indicating fast kinetics.
• All transitions were reversible upon decompression, with no observed chemical decomposition.

Conclusions:

• Compression rate has minimal impact on the structural response of β-HMX.
• Static high-pressure data can inform the behavior of β-HMX under dynamic conditions.
• Results contribute to improved safety predictions and kinetic initiation models for β-HMX-based explosives.