We investigate the evolution of the fluorite structure in the Ce_1-xM_xO_2-x/2 system with Gd and Sm as Rare Earth (RE) doping cations and Gd/Sm as co-doping couple using Molecular Dynamics at 298 K. Doping cations and oxygen vacancies are introduced in the CeO₂ fluorite lattice through two different arrangements the Random one and the Neighbour one. The evolution of the lattice parameter is compared with different models and experimental data extracted from the literature. Results concerning the chemical expansion and the oxygen vacancy radius are commented. The calculation of the Radial Distribution Function (RDF) allows to observe two components for the Ce-Ce, Ce-M and M-M (M = Gd, Sm, Gd/Sm) bond length as it is the case in the C-type RE₂O₃ structure. The percolation concept is introduced and discussed based on the evolution of the M-M group size distribution and the M-O coordination number.

我们使用分子动力学在298 K下研究了以Gd和Sm为稀土（RE）掺杂阳离子和Gd / Sm为共掺杂对的Ce _1-x M _x O _{2-x / 2}系统中萤石结构的演化。在CeO ₂中引入了掺杂阳离子和氧空位萤石晶格通过两种不同的排列方式，随机一和邻居一。将晶格参数的演变与不同的模型进行比较，并从文献中提取实验数据。评论了有关化学膨胀和氧空位半径的结果。径向分布函数（RDF）的计算允许观察到Ce-Ce，Ce-M和MM的两个分量（M = Gd，Sm，Gd / Sm）键长，就像在C型RE中一样₂ O ₃结构。渗滤概念是基于MM组大小分布和MO协调数的演变而引入和讨论的。