First-Principles Studies of Structural Evolutions in Cathode Materials LiMO_(2)(M=Co,Mn,Ni)  

作　　者：Yufeng Sun Xin-Gao Gong Ji-Hui Yang 孙瑜锋;龚新高;杨吉辉(Key Laboratory for Computational Physical Sciences(MOE),Department of Physics,Fudan University,Shanghai 200433,China;Shanghai Qizhi Institution,Shanghai 200232,China)

机构地区：[1]Key Laboratory for Computational Physical Sciences(MOE),Department of Physics,Fudan University,Shanghai 200433,China [2]Shanghai Qizhi Institution,Shanghai 200232,China

出　　处：《Chinese Physics Letters》2024年第10期129-136,共8页中国物理快报（英文版）

基　　金：partially supported by the National Key R&D Program of China(Grant No.2022YFA1404603);the National Natural Science Foundation of China(Grant Nos.12188101 and 11991061);the Guangdong Major Project of the Basic and Applied Basic Research(Grant No.2021B0301030005)。

摘　　要：We explore the structural evolutions of stoichiometric LiMO_(2)using the first-principles calculations combined with the cluster expansion method.We automatically obtain the ground state structures of the stoichiometric LiMO_(2)by just considering the cation orderings in the quasi rock-salt structures and the following structural relaxations due to both the atomic size mismatches and the Jahn–Teller distortions.We point out that,on the one hand,the cation orderings are mainly determined by the nearest,the second nearest,and the third nearest cation interactions and can be obtained from the‘phase diagram’we have built using the relative strengths of effective cluster interaction(ECI).On the other hand,the structural relaxations are dominated by the crystal field splitting(CFS)energies,i.e.,structures with larger CFS energies are more stable.By calculating the ECIs and CFS energies for various structures of LiMO_(2),we clearly show how ECI and CFS play roles in determining the structural evolution mechanism of these systems.

关 键 词：method RELAXATION CLUSTER 

分 类 号：O469[理学—凝聚态物理]