Molecule Empowerment and Crystal Desensitization: A Multilevel Structure-Property Analysis toward Designing...

Area of Science:

• Materials Science
• Chemistry
• Computational Chemistry

Background:

• Layered energetic materials (LEMs) offer a promising balance between high energy output and mechanical sensitivity.
• Current understanding of how layered stacking influences impact sensitivity is limited, hindering the design of advanced LEMs.
• Developing high-energy, low-sensitivity LEMs is crucial for safer energetic material applications.

Purpose of the Study:

• To investigate the relationship between molecular/crystal properties and the impact sensitivity of LEMs.
• To develop predictive models for the impact sensitivity of LEMs.
• To propose a novel design strategy for high-energy, low-sensitivity LEMs.

Main Methods:

• High-throughput screening of over 10^6 candidate structures using novel indicators like maximum plane separation and hydrogen bond dimension.
• Systematic analysis of structure-property relationships, focusing on bond dissociation energy (BDE), intralayer hydrogen bond energy (HBE), and sliding energy barrier (SEB).
• Development of a prediction model for impact sensitivity (R^2 = 0.88) and a linear model based on molecular features.

Main Results:

• Low impact sensitivity in LEMs requires at least two of the three key properties (BDE, HBE, SEB) to perform well.
• Interlayer sliding resistance can be reduced by strengthening intermolecular hydrogen bond interactions.
• Factors influencing HBE and SEB were identified, leading to a new design strategy: molecular empowerment and crystal desensitization.

Conclusions:

• A clear correlation exists between molecular-level properties, crystal-level characteristics, and the impact sensitivity of LEMs.
• The developed prediction model accurately forecasts LEM impact sensitivity.
• The proposed design strategy provides a new pathway for creating advanced high-energy, low-sensitivity energetic materials.