Calculating optoelectronic properties of halide perovskites with a first-principles tight-binding approach

Density functional theory (DFT) is a well-established theoretical tool helping to reveal origins of the fascinating optoelectronic properties of halide perovskites (HaPs). However, DFT presents too high computational costs for large-scale simulations of HaPs, which prompts us to search for an alternative theoretical approach. Therefore, following previous work [1] we propose a tight binding (TB) model as a computationally efficient tool to model large-scale system sizes and calculate optoelectronic properties of HaPs. By parametrizing the TB model with the help of DFT calculations and applying it to force-field molecular dynamics trajectories, we will demonstrate computation of optoelectronic properties, such as band gap distributions, for several HaPs. This helps rationalizing various interesting physical properties of HaPs, such as the coincidence of small Urbach energies and large amounts of dynamic disorder around room temperature.


References
[1] M. Z. Mayers, L. Z. Tan, D. A. Egger, A. M. Rappe and D. R. Reichman. How Lattice and Charge Fluctuations Control Carrier Dynamics in Halide Perovskites. Nano Lett. 18, 8041 – 8046 (2018).