First-principles structure prediction and chirality transfer in chiral organic-inorganic perovskite nanoplatelets*

Hybrid metal halide perovskites are innovative optoelectronic materials with outstanding quantum yields and are potential hosts of spin-splitting for spin-selective transport, photoluminescence, and spin-orbitronics. Structure-based chirality transfer from organic to inorganic components has been observed in bulk 2D hybrid organic-inorganic perovskites (2D HOIPs). Using a first-principles approach, we here elucidate the structure and spin nature of perovskite nanoplatelets with surface chiral ligands (R-/S-β-methylphenethylamine). We conduct a systematic geometry search and a series of DFT-based high-throughput structure relaxations, trying to enumerate the likely organic-inorganic conformations. Within the range of thermal fluctuations at room temperature, we identify chiral distortion patterns shared by the most stable structures. The following band structure and spin-texture calculations show distortion-induced spin-splitting, supporting the optical chirality observed in the experiments.