The _atom_site_B_iso_or_equiv values (in Ų) indicate atomic vibration:
The cubic (or near-cubic) black phase. This is the photoactive phase used in solar cells because its bandgap (~1.48 eV) is nearly ideal for capturing sunlight. fapbi3 cif file
eV, which is the "sweet spot" for converting sunlight into electricity with maximum efficiency. 2. The Structural Drama: If you open an FAPbI fapbi3 cif file