Luminescent properties and Hirshfeld surface analyses of two new 3D Zn(II) coordination polymers assembled from isomeric terpyridyl carboxylate derivative and terephthalate ligands

Abstract

Two new coordination polymers having compositions [Zn(4-cmopt)(tp)_0.5]_n (1) and [Zn(3-cmopt)(tp)_0.5]_n (2) (4-Hcmopt = 4′-(4-carboxy-methoxyphenyl)-4,2′:6′,4″-terpyridine, 3-Hcmopt = 4′-(4-carboxy-methoxyphenyl)-3,2′:6′,3″-terpyridine and H₂tp = terephthalic acid), have been designed and synthesized by altering the structure features in terpyridine moieties under similar hydrothermal reaction conditions and characterized by elemental analysis, FTIR and single crystal X-ray diffraction techniques. The single crystal X-ray diffraction studies indicate that 1 displays an unusual 3D coordination network which exhibits an intriguing two-fold interpenetrating new (3,4)-connected binodal topological net with the Schläfli symbol of (4.8².10³)(4.8²). While, 2 features an unusual three-fold interpenetrating 3D coordination network displaying an interesting new (3,4)-connected ins topological net with the Schläfli symbol of (6³)(6⁵.8). The structural differences in both CPs provide apt insights into the effect of the positional isomeric structures of terpyridyl derivative ligands on the construction of coordination polymers. Additionally, the thermal stabilities and photoluminescence properties of 1 and 2 have been studied and the Hirshfeld surface analyses have been performed to assess their lattice properties.