中国物理B ›› 2024, Vol. 33 ›› Issue (8): 86601-086601.doi: 10.1088/1674-1056/ad5d9a
Aming Lin(林啊鸣)1,2, Jing Shi(石晶)3, Su-Huai Wei(魏苏淮)4,†, and Yi-Yang Sun(孙宜阳)1,2,‡
Aming Lin(林啊鸣)1,2, Jing Shi(石晶)3, Su-Huai Wei(魏苏淮)4,†, and Yi-Yang Sun(孙宜阳)1,2,‡
摘要: Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes. Computational methods, specifically nudged elastic band (NEB) and molecular dynamics (MD) methods, provide powerful tools for the design of solid-state electrolytes. The MD method is usually the choice for studying the materials involving complex multiple diffusion paths or having disordered structures. However, it relies on simulations at temperatures much higher than working temperature. This paper studies the reliability of the MD method using the system of Na diffusion in MgO as a benchmark. We carefully study the convergence behavior of the MD method and demonstrate that total effective simulation time of 12 ns can converge the calculated diffusion barrier to about 0.01 eV. The calculated diffusion barrier is 0.31 eV from both methods. The diffusion coefficients at room temperature are $4.3\times 10^{-9}$ cm$^2\cdot$s$^{-1}$ and $2.2\times 10^{-9}$ cm$^2\cdot$s$^{-1}$, respectively, from the NEB and MD methods. Our results justify the reliability of the MD method, even though high temperature simulations have to be employed to overcome the limitation on simulation time.
中图分类号: (Diffusion of impurities ?)