-FAPbI3 (Black phase) : The cubic perovskite structure (space group ) used for high-efficiency solar cells.
Unlike the simpler cesium cation, the formamidinium (FA) molecule is a large, non-spherical organic cation. In a standard cubic CIF, the FA molecule often appears because it rotates rapidly within the lead-iodide "cage". This requires researchers to choose between a "time-averaged" CIF (useful for standard XRD refinement) and a "frozen" or relaxed structure (often derived from DFT calculations ) for modeling electronic band structures. Strategic Importance FAPbI3.cif - WMD-group/hybrid-perovskites - GitHub fapbi3 cif file
loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy Pb Pb 0.00000 0.00000 0.00000 1.0 I I 0.00000 0.00000 0.50000 1.0 FA C 0.50000 0.50000 0.50000 1.0 FA N 0.50000 0.50000 0.50000 0.5 # simplified representation -FAPbI3 (Black phase) : The cubic perovskite structure
Key papers (e.g., by Weber or Kanatzidis) often include CIFs as Supplementary Information. fapbi3 cif file