Effect of Charge on the Structures of Zn(II) Coordination Polymers with Triazole-carboxylate Ligands: Syntheses, Structures, and Luminescent Properties

Three new Zn(II) coordination polymers, {[Zn(L1)2(H2O)2]·4H2O}n (1), {[Zn(L2)(H2O)2]·0.5H2O}n (2), and {[Zn1.5(L1)(o-bdc)(H2O)]·0.5H2O}n (3) (HL1 = 3,5-di(1,2,4-triazol-1-yl)benzoic acid, H2L2 = 5-(triazol-1-yl)isophthalic acid, o-H2bdc = 1,2-benzenedicarboxylic acid), were successfully synthesized and characterized. Compound 1 exhibits 1D chain structure containing [Zn(L1)2] unit. Compound 2 shows a 2D plane with the ratio of Zn:L2 was 1:1 since L2 can match the positive charge of Zn(II). When L1 and o-bdc2– were presented together, Zn(II) centers are linked by L1 to form 2D double layers, then o-bdc2– further connected the adjacent layers to generate final 3D framework of 3. The ligand charges may play key roles in tuning the frameworks of compounds 1–3. The solid state luminescence of compounds 1–3 and all ligands have been investigated here.