Advances in the modelling and simulation of high-energy density materials

With the development of simulation technique and the rapid advances in computing power, modelling and simulation (M&S) began to demonstrate vast potential in predicting the properties of energetic material and helping to design potential energetic material. The prediction of energetic material density has evolved from evaluating molecular volume using Monte Carlo integration to the calculations of material density at the crystal scale: a technique, incorporating crystal packing and crystalline structure prediction through the first principles simulation, has demonstrated the ability to distinguish different polymorphs of energetic molecules and accurately predict their crystal structure and density. The atomization scheme together with high-level calculational models can predict most energetic materials with minimal reliance on reference systems and limits. In addition to its ability to predict detonation pressures and velocities of well-established classes of energetic materials based on the thermochemical code or empirical equations. M&S has proven effective in screening the potential of newly designed energetic materials. The application of M&S significantly enhances safety by reducing the number of hazardous experiments needed for material development. The ability to screen materials based on M&S predicted HOFs and detonation properties reduces experimental frequency, thereby decreasing both the risk of hazardous tests and overall development costs.

Gaussian, VASP, and EXPLO5™ were utilized. The optimization and QM density predictions for energetic molecules were performed at the level of DFT B3LYP using Gaussian 16. While the determination of crystal structure and crystal density was performed using VASP 6. Subsequently, the heat of formation calculation was performed using Gaussian 16 at the G2 and CBS-Q level. EXPLO5™ code enabled the calculation of detonation velocity and detonation pressure.