Nitroaliphatic compounds constitute an important class of energetic materials, and their impact sensitivity
(h50%) is a key parameter for evaluating the safety of these compounds under mechanical shock.
In this study, nonlinear quantitative structure-property relationship (QSPR) models are developed to accurately predict
the impact sensitivity of nitroaliphatic compounds, providing a reliable alternative to experimental testing for safety
assessment of energetic materials.
Three key molecular descriptors previously screened by Prana are employed to construct four nonlinear QSPR models:
random forest (RF), linear mixed-kernel support vector regression (LMIX-SVR), Gaussian process regression (GPR),
and linear multilayer perceptron (L-MLP). Model performances are comprehensively evaluated through internal validation,
external validation, and applicability domain analysis.
Overall, models based on kernel methods with smooth distance metrics (GPR and LMIX-SVR) or lightweight regularized neural
networks (L-MLP) demonstrate superior fitting ability and prediction robustness. Among them, the L-MLP model exhibits the
best overall performance, with a coefficient of determination of
RTrain2 = 0.9040 and root-mean-square error
RMSETrain = 0.1406 for the training set; for the external validation set,
REXT2 = 0.8343 and
RMSEEXT = 0.1720; and cross-validation results of
QLOO2 = 0.8511 and
Q5CV2 = 0.8526.
Within the applicability domain, for the internal validation set, the L-MLP model achieves
RIN2 = 0.8073 and
RMSEIN = 0.1776, demonstrating significantly higher prediction accuracy than the conventional multiple linear
regression model. These results indicate that nonlinear QSPR models based on simple structural descriptors can effectively
capture the complex structure¨Cproperty relationships governing impact sensitivity.
In particular, the L-MLP model combines the interpretability of linear models with the nonlinear fitting capability of
neural networks, offering a reliable methodological reference for rapid prediction of the impact sensitivity of
nitroaliphatic compounds and for safety screening of energetic materials.