Syntheses, Crystal Structures, and Fluorescence Properties of Two 2D→2D Coordination Polymers Based on the Flexible 4-Substituted Bis(1,2,4-triazole) Ligand

Two new 2D → 2D zinc(II) coordination polymers, [Zn(btre)0.5(nbdc)(H2O)]n (1) and {[Zn(btre)0.5(MeOip)(H2O)2]·H2O}n (2) (btre = 1,2-bis(1,2,4-triazol-4-yl)ethane, nbdc=3-nitro-1, 2-benzenedicarboxylate, MeOip=4-methoxybenzene-1, 3-dicarboxylate) were synthesized at room temperature condition and characterized by IR spectra, elemental analyses, single-crystal and powder X-ray diffractions. Three sets of equivalent 2D (6, 3) networks parallel polycatenated with each other to give a 2D → 2D network in 1 and 2. There are strong π-π interactions and hydrogen bonding interactions between adjacent parallel polycatenated 2D (6, 3) network in 1. Only hydrogen bonding interactions exist in 2. Thermal stabilities and luminescence of 1 and 2 were investigated.