The syntheses, structures and fluorescent properties of two monomeric Zn(II) and Mn(II) assemblies containing bitriazole ligand

Two monomeric complexes, [Zn(trtr)2(H2O)4](NO3)2 · 2H2O (1) and [Mn(trtr)2(H2O)4](ClO4)2 (2), were obtained from the reactions of bitriazole ligand 4-[3-(1,2,4-triazolyl)-1,2,4-triazole] (trtr) with Zn(NO3)2 and Mn(ClO4)2, respectively. A 3-D supramolecular framework of 1 is constructed by the hydrogen bonds with lattice water molecule as linkers. In 2, a 2-D supramolecular layer is formed by hydrogen bonding interactions between the monomeric assembly and image, and further connected into a 3-D framework by d⋯π and π⋯π stacking interactions. The coordination of the metal centers to the new born triazole ring play an important role in their fluorescent properties, which present the emission peaks at 349 nm and 358 nm, respectively, originated from LMCT.