Grammar of Impact Sensitivity: An Incremental Theory

Area of Science:

• Computational Chemistry
• Materials Science
• Chemical Engineering

Background:

• Impact sensitivity is a critical safety parameter for energetic materials.
• Existing methods for quantifying impact sensitivity often rely on extensive experimental testing.
• Predictive models for impact sensitivity are needed to accelerate materials discovery and safety assessments.

Purpose of the Study:

• To develop and validate a quantitative structure-property relationship (QSPR) model for predicting the impact sensitivity of energetic materials.
• To introduce a second-order incremental approach based on molecular structural features to predict impact height (h50).
• To demonstrate the feasibility of calculating impact sensitivity using computational methods.

Main Methods:

• Development of a second-order incremental approach correlating molecular structural increments with impact height (h50).
• Utilized a large dataset of 450 energetic materials (nitro compounds, peroxides, nitrogen-rich salts, heterocycles) for model development.
• Employed machine-based regression analysis, including genetic function approximation, multiple linear regression, and artificial neural networks, for validation.

Main Results:

• The proposed incremental method shows a noticeable correlation with experimental impact height (h50) values.
• Achieved R² values of 0.56 for the training set and 0.63 for the test set, with corresponding RMSEs of 12.5 J and 18.8 J.
• The model's accuracy can be improved by extending the number of structural increments and refining coefficients.

Conclusions:

• The developed second-order incremental approach provides a reliable and calculable method for predicting the impact sensitivity of energetic materials.
• This approach significantly enhances the understanding of impact sensitivity phenomena.
• The method allows for impact sensitivity to be calculated using basic computational tools, reducing the need for extensive experimentation.