RT journal article
T1 Transferable Classical Force Field for Pure and Mixed Metal Halide Perovskites Parameterized from First-Principles
A1 Seijas-Bellido, Juan Antonio
A1 Samanta, Bipasa
A1 Valadez-Villalobos, Karen
A1 Gallardo Bernal, Juan Jesús
A1 Navas Pineda, Francisco Javier
A1 Balestra, Salvador R. G.
A1 Madero Castro, Rafael María
A1 Vicent-Luna, José Manuel
A1 Tao, Shuxia
A1 Toroker, Maytal Caspary
A1 Anta, Juan Antonio
A2 Química Física
AB Many key features in photovoltaic perovskites occur in relatively long time scales and involve mixed compositions. This requires realistic but also numerically simple models. In this work we present a transferable dassical force field to describe the mixed hybrid perovskite MA(x)FA(1)-xPb(BryI1-y)(3) for variable composition (for all x, y is an element of [0, 1]). The model includes Lennard-Jones and Buckingham potentials to describe the interactions between the atoms of the inorganic lattice and the organic molecule, and the AMBER model to describe intramolecular atomic interactions. Most of the parameters of the force field have been obtained by means of a genetic algorithm previously developed to parametrize the CsPb(BrxI1-x)(3) perovskite (Balestra et al. J. Mater. Chem. A. 2020, DOI: 10.1039/d0ta03200j). The algorithm finds the best parameter set that simultaneously fits the DFT energies obtained for several crystalline structures with moderate degrees of distortion with respect to the equilibrium configuration. The resulting model reproduces correctly the XRD patterns, the expansion of the lattice upon I/Br substitution, and the thermal expansion coefficients. We use the model to run classical molecular dynamics simulations with up to 8600 atoms and simulation times of up to 40 ns. From the simulations we have extracted the ion diffusion coefficient of the pure and mixed perovskites, presenting for the first time these values obtained by a fully dynamical method using a transferable model fitted to first-principles calculations. The values here reported can be considered as the theoretical upper limit, that is, without grain boundaries or other defects, for ion migration dynamics induced by halide vacancies in photovoltaic perovskite devices under operational conditions.
PB AMER CHEMICAL SOC
SN 1549-960X
YR 2022
FD 2022-05
LK http://hdl.handle.net/10498/27538
UL http://hdl.handle.net/10498/27538
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 11-nov-2026