2021/10/31 by Cecilia Vona, Vona, Cecilia, Dmitrii Nabok +3 · 2 citations
Engineering · Physics and Astronomy · #Perovskite Materials and Applications #Semiconductor Quantum Structures and Devices
paper · pdf · doi:10.48550/arxiv.2111.00503
Organic-inorganic metal halide perovskites (HaPs) are intensively studied for\ntheir light-harvesting properties. Owing to the interplay between strong\nelectron-electron interaction and spin-orbit coupling (SOC), their quantitative\ntheoretical description is still a challenge as evidenced by the wide variety\nof results available in literature. Here, various methodologies for computing\ntheir electronic structure are evaluated, also accounting for SOC. More\nspecific, the GW approach as well as variants of the hybrid functionals PBE0\nand HSE are at the center of our investigations. For both functionals, we\nexplore methods to determine the mixing parameter \α, and for HSE, we\ninvestigate the impact of the screening-parameter \ω. An extensive\ninvestigation of PbI2, a precursor of many HaPs, leads to the conclusion that\nhybrid functionals with \α tuned by the density-based mixing method are\nmost suitable for obtaining band gaps comparable to G0W0 results. Moreover,\nthis methodology is transferable to CsPbI3, and the same behaviour is expected\nfor the entire family of lead-iodine perovskites.\n