The application of Variable Reaction Coordinate Transition State Theory for an energetic material is presented. The homolysis of the N–N bond in RDX is characterized using an embedding methodology in which key atoms in the bond-dissociation process are computed using CASPT2(10e,7o)/jun-cc-pVTZ, while the rest of the molecule is computed using M06-2X/jun-cc-pVTZ. Microcanonical rate theory is used to quantify the temperature and pressure dependent rate constants. The cleavage of the N–N bond is by far the dominant channel, with HONO elimination a distant second. The predicted rate constants are in excellent agreement with the experimental data. The computational approach can be used to provide accurate models for the combustion properties of novel energetic materials.

提出了变反应坐标过渡态理论在高能材料中的应用。使用包埋法表征RDX中N–N键的均解，其中键离解过程中的关键原子是使用CASPT2（10e，7o）/ jun-cc-pVTZ计算的，而其余分子则是计算的使用M06-2X / jun-cc-pVTZ。微规范速率理论用于量化温度和压力相关的速率常数。迄今为止，N–N键的断裂是主要的通道，而HONO的消除则遥遥领先。预测的速率常数与实验数据非常吻合。该计算方法可用于为新型高能材料的燃烧特性提供准确的模型。