Molecular dynamics study of composition-dependent intermolecular interactions and trigger-bond stability in DNTF/HMX...

Area of Science:

• Materials Science
• Computational Chemistry
• Energetic Materials

Background:

• Intermolecular compatibility is crucial for the performance of DNTF/HMX melt-cast explosives.
• The composition-dependent nature of this compatibility requires detailed investigation.

Purpose of the Study:

• To investigate the composition dependence of intermolecular compatibility in DNTF/HMX mixtures.
• To determine the optimal mass ratio for enhanced cohesive and mechanical properties.

Main Methods:

• Simulated periodic DNTF/HMX amorphous models across various mass ratios (21:79 to 71:29) using Materials Studio and COMPASS II.
• Evaluated binding energy, cohesive energy density, C-H···O contacts, and elastic parameters.
• Performed dimer analysis and electronic structure calculations for interaction energies and noncovalent interactions.

Main Results:

• The 41:59 DNTF/HMX mass ratio exhibited the highest normalized binding energy and cohesive energy density.
• This ratio also showed the most heteromolecular C-H···O contacts and favorable elastic properties (Pugh and Poisson ratios).
• The 41:59 composition suppressed unfavorable bond length distributions in DNTF.

Conclusions:

• The 41:59 mass ratio provides the best balance of heteromolecular cohesion and deformation adaptability in DNTF/HMX mixtures.
• This composition offers enhanced mechanical response and stability for melt-cast explosives.
• Computational modeling effectively predicts optimal compositions for energetic materials.