Self-assembly of three d10 metal coordination polymers based on a flexible bis(2-methylbenzimidazole) and dicarboxylate co-ligands

Hydrothermal self-assembly of zinc nitrate with 1,1′-(1,3-propane)bis-(2-methylbenzimidazole) (pbmb) and different dicarboxylic acid ligands gave rise to three new coordination polymers [Zn(pbmb)(hmph)]n (1), {[Zn2(pbmb)(chdc)2]⋅0.5H2O}n (2), [Zn(pbmb)(mip)]n (3) (H2hmph = homophthalic acid, H2chdc = 1,4-cyclohexanedicarboxylic acid and H2mip = 5-methylisophthalic acid). Both complexes 1 and 3 possess 2D {63} framework and further extend into 3D supramolecular network via CH⋯O hydrogen bonding or π–π stack interactions. While 2 is a 1D double loop-like chain structure, which arranged into a 2D network through CH⋯O hydrogen bonding interactions. Three compounds all exhibit strong photoluminescence at room temperature in solid state and may be good candidates for potential luminescence materials.