One- and Two-Dimensional Iodine-Rich Iodobismuthate(III) Complexes: Structure, Optical Properties, and Features of Halogen Bonding in the Solid State

Reactions of BiI 3, I 2, and iodide salts of two different pyridinum cations result in the formation of the novel iodine-rich iodobismuthates(III) (1,3-MePy) 4 {[Bi 4 I 16 ](I 2 )} ( 1 ) and (1-MePy){[BiI 4 ](I 2 ) 0.5 ) ( 2 ), where the halometalate anions are connected by diiodine linkers into one- or two-dimensional supramolecular structures. Both complexes reveal narrow optical band gaps and fairly high thermal stability, favoring their potential use in photovoltaic devices.