Polymorphism and Structural Filiations in Five New Organic–Inorganic Hybrid Salts of the Heteroleptic Cationic Iridium(III) Complex and Polyoxometalates

Five new hybrid compounds ionically associating the phosphorescent heteroleptic cationic iridium(III) complex [IrIII(ppy)2(bpy)]+ ([Ir]+) (ppy = 2-phenylpyridine, bpy = 2,2′-bipyridine) and anionic polyoxometalates (POMs) units have been successfully elaborated, namely, [Ir]2[W6O19]·H2O (m-Ir2W6), [Ir]2[W6O19] (t-Ir2W6-2), [Ir]2[Mo6O19] (t-Ir2Mo6-2), [Ir]4[α-Mo8O26]·4DMF·5H2O (Ir4αMo8DMF), and [Ir]2(HDMA)2[β-Mo8O26]·2DMF·H2O (HDMA+ = dimethylammonium) (Ir2βMo8HDMA). These systems differ by the composition and the topology of the POMs, the [Ir]+/POM ratio, the nature of the other counter-cations, and the presence or not of crystallized solvent molecules. Their crystal structures and their photoluminescent properties have been determined and compared with those of a previously reported series of [Ir]+/POM assemblies revealing polymorphism and structural filiations. The emission properties of the compounds are strongly modulated by the nature of the POM units and the crystal packing of the hybrid frameworks.