Type structure, which is composed of organic diammonium, triiodide and hexaiodobismuthate, varies according to different structures of incorporated cations

Type structure of (H3N–R–NH3)2I3BiI6, which consists of sheets of organic entities together with triiodide anions separated by layers of BiI6 octahedra, is defined by triiodide, hexaiodobismuthate, and organic diammonium. The prototype structure of (H3N(CH2)2SS(CH2)2NH3)2I3BiI6 (1) can accommodate various changes according to the nature of the organic group, such as conformation, length or size. In (H3N(CH2)2SS(CH2)2NH3)2I3BiI6·0.5H2O (2), acentric symmetry resulted from the lattice water molecules render the SHG property. Whereas in (H3N(CH2)4NH3)2(I3)0.5(I(H2O)2)0.5 BiI6 (3), water molecules are incorporated in the main framework by substituting two iodine atoms of I3− anion, in the structure of (H3NCH2(C6H10)CO2H)4(I3)2BiI6 H3O (4), pairs of linear triiodide entities [I3⋯I3]2− (d(I3−⋯I3−) = 3.77(1) Å) are observed, owing to the super-long diammonium cations of two trans-4-methylammonium cyclohexane carboxylic acid linked together via hydrogen bonding between carboxylate groups.