title: (C4H3SCH2NH3)2(CH3NH3)Pb2I7: non-centrosymmetrical crystal structure of a bilayer hybrid perovskite.
abstract: The analysis of the crystal structure of (C4H3SCH2NH3)2(CH3NH3)Pb2I7, displaying a well-ordered acentric inorganic Pb2I7(3-) bilayer, is reported, and compared to the related monolayer hybrid perovskite.