Quantum mechanical molecular dynamics simulations of polaron formation in methylammonium lead iodide perovskite

Abstract

Polaron formation in a halide perovskite is analyzed via nanometre-scale quantum mechanical molecular dynamics simulations.

Picosecond Charge Localization Dynamics in CH3NH3PbI3 Perovskite Probed by Infrared-Activated Vibrations

“…26−28 A two-step localization process has recently been inferred from calculations. 29 Initially, the excess charge is localized by local thermal fluctuations of the structure. In a second step, the charge affects its surroundings, leading to further distortion of the inorganic lattice and reorientation of MA cations, thus completing the localization process.…”

Multiple protonation states in ligand-free SARS-CoV-2 main protease revealed by large-scale quantum molecular dynamics simulations

“…The QMD/MetaD simulations for large-scale systems including more than 10000 atoms can be achieved using the divide-and-conquer density-functional tight-binding (DC-DFTB) method [29] , [30] . Thus far, DC-DFTB-MD/MetaD simulations have been successfully applied to solutions [31] , [32] , batteries [33] , [34] , perovskites [35] , catalysts [36] , [37] , and biomolecular systems [38] , [39] . Here, the DC-DFTB-MD/MetaD and free energy analysis revealed that the functionally relevant IP state consistent with neutron crystallography [28] pre-exists even without ligands, and that this IP state is the most stable protonation state.…”

Spin‐flip approach within time‐dependent density functional tight‐binding method: Theory and applications

“…Recently, quantum chemical simulations of systems with more than 1,000 atoms were accomplished by utilizing multilayer and linear‐scaling methods . Also, our original linear‐scaling program for the massive parallel architecture, DCDFTBMD, was successful in describing various chemical phenomena in complex systems . However, application of the DFTB method to (quasi‐)degenerate phenomena has rarely been reported …”