New accurate molecular dynamics potential function to model the phase transformation of cesium lead triiodide perovskite (CsPbI₃)

Abstract

The new hybrid potential of CsPbI3 accurately reproduces the density, structure and phase transformation from orthorhombic to cubic crystal structure.

Long-Range Binding of Defect Clusters Leads to Suppressed Ion Mobility in Cs-Doped Methylammonium Lead Iodide

“…Winkler potential was used to define all of the inorganic interactions . Short-range l – j potential parameters of Cs were obtained from ref . Buckingham potential parameters were converted to l – j parameters of Cs by fitting against the lattice parameters of CsPbI 3 .…”

Critical Evaluation of Five Classical Force Fields for CsPbI3: Limitations in Modeling Phase Stability and Transformations

“…In the EABC potential, the Cs–Pb, Cs–I, Pb–I, and I–I interactions are described by the B-Coul potential as in eq , while the Buckingham potential is replaced by EAMs for the Cs–Cs and Pb–Pb interactions. Most of the force field parameters in EABC were taken from different existing force fields . It is important to note that the Coulombic interactions in the EABC force field are short-range potentials with a cutoff radius of 12 Å.…”

“…As perovskite materials are still considered relatively new, the development of force fields for CsPbI 3 and other perovskite systems remains limited. To date, force fields for CsPbI 3 materials mainly fall into five categories: rigid ion models (RIMs), , many-body force fields, polarizable force fields, reactive force fields, and machine learning force fields (MLFF). − Among these, the first four belong to classical force fields and are the focus of the evaluation in this study. Although machine learning force fields are rapidly developing and hold great potential, their simulation was not included in this work due to the limited availability of force field files and the corresponding MD software packages.…”

“…Balestra et al have developed a B-Coul force field for CsPbI 3 to investigate the lattice dynamics and ion migration in inorganic perovskites. Almishal et al pointed out that the B-Coul potential alone cannot accurately describe the structural properties and phase transitions of CsPbI 3 , but the addition of Cs–Cs and Pb–Pb EAM many-body potentials on top of the B-Coul potential can improve the prediction accuracy of the crystal structures. Rathnayake et al have developed a polarizable AMOEBA force field for the CsPbI 3 -solvent system, enabling the study of crystal nucleation, growth, and ion solvation in the CsPbI 3 solutions. ,, Pols et al have developed a ReaxFF force field for CsPbI 3 and have used it to investigate the degradation of CsPbI 3 at high temperatures.…”

“…In this study, we evaluate the five classical force fields developed for CsPbI 3 : LJ-Coul, B-Coul, EABC, AMOEBA, and ReaxFF . We compare their abilities and accuracy in predicting the stability and phase transitions of the CsPbI 3 polymorphs.…”