Cui Chuan-Xin, Jiang Jin-Wu
Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Frontier Science Center of Mechanoinformatics, School of Mechanics and Engineering Science, Shanghai University, Shanghai 200072, People's Republic of China.
Zhejiang Laboratory, Hangzhou 311100, People's Republic of China.
J Chem Phys. 2024 Sep 14;161(10). doi: 10.1063/5.0221731.
The CsPbI3 perovskite is a promising candidate for photovoltaic applications, for which several critical phase transitions govern both its efficiency and stability. Large-scale molecular dynamics simulations are valuable in understanding the microscopic mechanisms of these transitions, in which the accuracy of the simulation heavily depends on the empirical potential. This study parameterizes two efficient and stable empirical potentials for the CsPbI3 perovskite. In these two empirical potentials, the short-ranged repulsive interaction is described by the Lennard-Jones model or the Buckingham model, while the long-ranged Coulomb interaction is summed by the damped shifted force method. Our molecular dynamics simulations show that these two empirical potentials accurately capture the γ ↔ β ↔ α and δ → α phase transitions for the CsPbI3 perovskite. Furthermore, they are up to two orders of magnitude more efficient than previous empirical models, owing to the high efficiency of the damped shifted force truncation treatment for the Coulomb interaction.
CsPbI3钙钛矿是光伏应用中一个很有前景的候选材料，其效率和稳定性受几个关键的相变过程控制。大规模分子动力学模拟对于理解这些相变的微观机制很有价值，其中模拟的准确性在很大程度上取决于经验势。本研究为CsPbI3钙钛矿参数化了两种高效且稳定的经验势。在这两种经验势中，短程排斥相互作用由Lennard-Jones模型或Buckingham模型描述，而长程库仑相互作用则通过阻尼移位力法求和。我们的分子动力学模拟表明，这两种经验势准确地捕捉到了CsPbI3钙钛矿的γ↔β↔α和δ→α相变。此外，由于对库仑相互作用采用了高效的阻尼移位力截断处理，它们比以前的经验模型效率提高了两个数量级。
