Synthesis and characterization of two new triazolate–aliphatic dicarboxylate bridged Zn(II) coordination polymers based on 2D layer motifs with different crystal packing

Abstract

Two new zinc(II)–triazole–aliphatic dicarboxylate coordination polymers, [Zn(trz)(Hsuc)] n ( 1), [Zn 2(trz) 2(tar)] n ( 2), have been hydrothermally synthesized by reaction of Zn salt, Htrz with H 2suc and H 2tar, respectively (Htrz = 1,2,4-triazole, H 2suc = succinic acid, H 2tar = tartaric acid). Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by X-ray powder diffraction, elemental analyses, IR spectra and TG analyses. Compound 1 displays a 2D layer structure containing {[Zn 4(trz) 4] 4+} n layers decorated by the suc ligand. Compound 2 is in a 3D structure formed by the interconnection of 2D {[Zn 4(trz) 4] 4+} n layers with tar ligand, resulting a 3,4-connected topological network. Due to the different coordination mode and conformation of aliphatic carboxylate ligand, the similar 2D {[Zn 4(trz) 4] 4+} n layers stack in the –AAA– fashion in 1, while the {[Zn 4(trz) 4] 4+} n layers hold together in the –ABAB– stacking sequence in 2. Additionally, the two compounds show strong fluorescence in the solid state at room temperature.