中文摘要：

采用基于密度泛函理论（DFT）下的的第一性原理,通过Sr原子代替Ce原子、F原子替代O原子,建立同等条件下纯净的、Sr单掺杂、Sr-F共掺杂的2×2×1模型,并对其晶体结构进行优化,计算并分析了体系的几何结构、能带结构、态密度和紫外屏蔽特性。计算结果表明：掺杂导致晶格体系发生畸变,体积增大;引入了杂质能级,能带变密,禁带宽度增大;CeO2紫外屏蔽增强,吸收谱线蓝移,紫外吸收阈值取决于O原子的2p轨道电子激发到Ce原子4f轨道空带。

英文摘要：

Using the plane wave ultra-soft pseudo-potential method and based on the density function theory （DFT）, through one Sr atom instead of Ce atom, one F atom instead of O atoms, the pure, Sr, and Sr-F Co doped 2×2×1 model under the equal condition were set, and its crystal structure was optimized. The geometry, band structures, density of states and UV shielding property were calculated and analyzed. The calculated results show that the lattice of CeO2 distorts after doping, volume increases, Impurity level is introduced, which can lead to the variation of the band and band gap width. At the same time, the absorption spectrum of CeO2 is enhanced and the absorption spectrum is blue shifted. UV absorption threshold depends on the oxygen atom of the 2p orbitals of the electrons excited to the cerium atom 4f orbita.