Revealing the Low-Temperature Phase of FAPbI₃ Using a Machine-Learned Potential.

ABSTRACT: Formamidinium lead iodide (FAPbI₃) is a material of interest for its potential in solar cell applications, driven by its remarkable optoelectronic properties. However, the low-temperature phase of FAPbI₃ remains poorly understood, with open questions surrounding its crystal structure, octahedral tilting, and arrangement of formamidinium (FA) cations. Using our trained machine-learned potential in combination with large-scale molecular dynamics (MD) simulations, we provide a detailed investigation of this phase, uncovering its structural characteristics and dynamical behavior. Our analysis reveals the octahedral tilt pattern and sheds light on the rotational dynamics of FA cations in the low-temperature phase. Strikingly, we find that the FA cations become frozen in a

SUBMITTER: Dutta S 

PROVIDER: S-EPMC12532299 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature