1. Modification of a ReaxFF potential at short range for energetic materials
- Author
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Weiyi Li, Tao Wang, Wenhua Li, Jintao Wang, Wanxiao Guo, Zexin Jiang, Yilin Fang, Xiyao Yun, and Ning Gao
- Subjects
Molecular dynamics ,Potential modification ,Energetic materials ,Displacement cascade ,Density functional theory ,Ab initio molecular dynamics ,Military Science - Abstract
The ReaxFF can describe the properties of energetic materials (EMs) at equilibrium state, but does not work properly in simulating high-energy particle irradiation process because of its weak short-range interaction. In this paper, a modification was made for such a potential by connecting Ziegler-Biersack-Littmark (ZBL) potential to ReaxFF-lg through comparing to Density Functional Theory (DFT) results to accurately describe short-range interactions. After modification, the newly fitted ReaxFF-lg/ZBL potential predicts better the equation of state for EMs In displacement cascade simulations, comparing to results from ab initio molecular dynamics (AIMD), ReaxFF-lg/ZBL presented the similar transferred energy from a primary knock-on atom to surrounding atoms, better than the original ReaxFF-lg potential. Further large-scale displacement cascade simulations indicated ReaxFF-lg/ZBL could be applied for cascade simulations with PKA energy from less than 1 keV to high energy (e.g. 35 keV) cases, which is suitable for effectively simulating high-energy displacement cascades in EMs using molecular dynamics method.
- Published
- 2024
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