# Perspective: Theory and simulation of hybrid halide perovskites

## TL;DR

This paper reviews the complex challenges in modeling hybrid halide perovskites, highlighting their dynamic processes, anharmonic lattice behavior, and electronic effects, and offers guidelines for accurate simulations relevant to various hybrid materials.

## Contribution

It provides a comprehensive overview of the theoretical and simulation challenges in hybrid halide perovskites and proposes general guidelines for predictive modeling of these complex materials.

## Key findings

- Identification of key dynamic processes affecting perovskite behavior
- Discussion of simulation challenges like anharmonicity and metastability
- Guidelines for accurate first-principles modeling of hybrid materials

## Abstract

Organic-inorganic halide perovskites present a number of challenges for first-principles atomistic materials modelling. These `plastic crystals' feature dynamic processes across multiple length-scales and time-scales, which include: (i) transport of slow ions and fast electrons; (ii) highly anharmonic lattice dynamics with short phonon lifetimes; (iii) local symmetry breaking of the average crystallographic space group; (iv) strong relativistic (spin-orbit coupling) effects on the electronic band structure; (v) thermodynamic metastability and rapid chemical breakdown. These issues, which affect the operation of solar cells, are outlined in this perspective. We also discuss general guidelines for performing quantitative and predictive simulations of these materials, which are relevant to metal-organic frameworks and other hybrid semiconducting, dielectric and ferroelectric compounds.