Synthesis, Characterization, and Electronic Structures of Organically Templated Lead Halides with One- and Two-Dimensional Hybrid Structures, [(nbq)(PbI3)]n and {[(CH3)3NC2H4N(CH3)3]3(Pb6I18)}n

Abstract

Two new organically templated lead(ii) iodide complexes, [(nbq)(PbI3)]n 1 and {[(CH3)3NC2H4N(CH3)3]3(Pb6I18)}n 2, have been synthesized in the presence of aromatic and aliphatic quaternary ammonium compounds, N-(n-butyl)quinolinium (nbq+) and [(CH3)3NC2H4N(CH3)3]2+, respectively, acting as structure-directing agents. Both 1 and 2 consist of uncoordinated structure-directing agents and inorganic moieties bound to the organic structure-directing agents. In 1, an inorganic (PbI3–)n one-dimensional polyanion chain is built up by face-sharing of distorted PbI6 tetrahedra. The inorganic framework of 2 presents a two-dimensional arrangement that could be discussed in terms of [Pb3I10]4– building blocks. Static attractive interactions between organic countercations and inorganic moieties were revealed through the crystal packing. Density functional theory calculations indicate that 1 possesses semiconductor properties, tuned by the π-electrons of nbq+. In contrast, 2 is conductive in the direction of aliphatic quaternary ammonium moiety.