Properties of radiation defects and threshold energy of displacement in zirconium hydride obtained by new deep-learning potential  

作　　者：王玺 唐孟 蒋明璇 陈阳春 刘智骁 邓辉球 Xi Wang;Meng Tang;Ming-Xuan Jiang;Yang-Chun Chen;Zhi-Xiao Liu;Hui-Qiu Deng(School of Physics and Electronics,Hunan University,Changsha 410082,China;College of Materials Science and Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]School of Physics and Electronics,Hunan University,Changsha 410082,China [2]College of Materials Science and Engineering,Hunan University,Changsha 410082,China

出　　处：《Chinese Physics B》2024年第7期456-465,共10页中国物理B（英文版）

基　　金：Project supported by the Joint Fund of the National Natural Science Foundation of China–“Ye Qisun”Science Fund(Grant No.U2341251)。

摘　　要：Zirconium hydride(ZrH_(2)) is an ideal neutron moderator material. However, radiation effect significantly changes its properties, which affect its behavior and the lifespan of the reactor. The threshold energy of displacement is an important quantity of the number of radiation defects produced, which helps us to predict the evolution of radiation defects in ZrH_(2).Molecular dynamics(MD) and ab initio molecular dynamics(AIMD) are two main methods of calculating the threshold energy of displacement. The MD simulations with empirical potentials often cannot accurately depict the transitional states that lattice atoms must surpass to reach an interstitial state. Additionally, the AIMD method is unable to perform largescale calculation, which poses a computational challenge beyond the simulation range of density functional theory. Machine learning potentials are renowned for their high accuracy and efficiency, making them an increasingly preferred choice for molecular dynamics simulations. In this work, we develop an accurate potential energy model for the ZrH_(2) system by using the deep-potential(DP) method. The DP model has a high degree of agreement with first-principles calculations for the typical defect energy and mechanical properties of the ZrH_(2) system, including the basic bulk properties, formation energy of point defects, as well as diffusion behavior of hydrogen and zirconium. By integrating the DP model with Ziegler–Biersack–Littmark(ZBL) potential, we can predict the threshold energy of displacement of zirconium and hydrogen in ε-ZrH_(2).

关 键 词：zirconium hydride deep learning potential radiation defects molecular dynamics threshold energy of displacement 

分 类 号：TQ134.12[化学工程—无机化工] TL34[核科学技术—核技术及应用]