Three Zn(II)-triazole-H(3)btc complexes regulated by mixed ligands protonation upon stepwise crystallization

By reaction of a zinc salt, 1,3,5-benzenetricarboxylic acid (H(3)btc) and 1,2,4-triazole (Htrz) under hydrothermal conditions, three mixed ligands protonation-dominated crystals, showing a 3-D microporous framework for 1, a 3-D pillared-layer structure for 2, and a 1-D chain motif for 3, have been stepwise isolated by crystallization of the reaction mixture and evaporation of the filtrates.