本报告总结了前期针对低燃耗（15000/MWd/tU）下U3Si2晶内缺陷及其裂变产物迁移性质进行了第一性原理计算研究。其中，UN的晶内缺陷包括了空位缺陷、间隙原子缺陷等。裂变产物中由于固态裂变产物对燃料的裂变气体释放以及辐照肿胀特性影响较小，因此本报告暂不考虑。本报告选取Xe为裂变气体的待变开展了计算研究。

This report summarizes the previous first-principles calculations of U3Si2 intragranular defects and their fission product migration properties at low burnup (15000/MWd/tU). Among them, the intragranular defects of UN include vacancy defects and interstitial atomic defects. Among the fission products, solid fission products have little effect on the fission gas release and radiation swelling characteristics of the fuel, so this report does not consider them for the time being. In this report, Xe is selected as the fission gas to be transformed to carry out computational research.