Identifying Practical\nDFT Functionals for Predicting\n0D and 1D Organic Metal-Halide Hybrids

Low-dimensional organic metal-halide\nhybrids (LD-OMHHs)\nare a promising\nclass of materials for applications in optical, magnetic, and quantum\ninformation technologies. Computational understanding of these materials\nnecessitates reliable and efficient methods for property prediction,\nsuch as predicting the electronic band gap. This work systematically\nbenchmarks three density functional theory (DFT) functionals as well\nas the impact of spin–orbital coupling on the band gap predictions\nfor 110 experimentally reported LD-OMHHs. Surprisingly, the band gap\npredicted by the generalized gradient approximation (GGA) aligns similarly\nor better with experimentally measured values compared to two meta-GGA\nmethods. Furthermore, spin–orbital coupling shows a limited\nimpact on these predictions. The potential existence of significant\nexcitonic effects might explain the discrepancies between meta-GGA\nand experimental band gaps. Our research also reveals that the direct\nuse of the GGA functional can already be practical and efficient for\nhigh-throughput screening of LD-OMHHs with reasonable band gaps.