Reaction Network of Ammonium Perchlorate (AP) Decomposition: The Missing Piece from Atomic Simulations

Thedecomposition network of ammonium perchlorate (AP) is essentialfor combustion performance and safety of solid propellants, whilethe detailed reaction pathway during thermolysis is far from cleardue to the ultrafast and complex reactions involved. Herein, we presentdirect atomic simulations of AP thermal decomposition and proposea detailed decomposition network to fill the missing piece in thekinetic models by using a neural network model derived from ab initio calculations. The proton transfer is the dominantchannel (NH4 + ClO4 & RARR; NH3 +HClO4), which is also observed in previous mass spectraexperiments. In addition, gas products from decomposition play a criticalrole in promoting the decomposition of solid AP. For example, theH abstraction reaction by OH is found to be a critical pathway forAP decomposition. These simulations provide atomic insights into thecomplex reaction dynamics of AP and can be extended to investigatethe reaction mechanism of novel energetic materials.