Three-dimensional metal-organic network architecture with large pi-conjugated indolocarbazole derivative: Synthesis, supramolecular structure, and highly enhanced fluorescence

By combining anew, large T-conjugated bidentate ligand, 2,8-bis[2-(2-pyridyl)vinyl]-5, 11-di(2-ethylhexyl)-indolo[3,2-b]carbazole (BPVIC) with a [Cd(NCS)(2)](infinity) polymer chain, a novel supramolecular coordination polymer, [Cd-2(BPVIC)(2)(SCN)(4)](infinity), with network structure has been prepared. The crystal structures of the ligand and the coordination polymer were determined by X-ray crystallography. The crystallographic analyses revealed that drums formed by the ligands, Cd2+ cations, and SCN- anions are interconnected, leading to the formation of infinite three-dimensional networks. The pi-pi and C-H center dot center dot center dot pi interactions among the free ligands, acting as energy traps and increasing nonradiative decay, are eliminated effectively in the metal coordination polymer. The metal coordination polymer exhibits strong luminescence in the yellow region and therefore is a potential luminescent material.