Inorganic Chemistry, Vol.59, No.5, 2680-2688, 2020
Structural Diversity of Copper(I) Cluster-Based Coordination Polymers with Pyrazine-2-thiol Ligand
Six novel copper(I) cluster-based coordination polymers (CPs) [Cu-9(pzt)(7)Cl-2](n) (1), [Cu-2(pzt)Cl](n) (2), [Cu-4(pzt)(3)Br](n) (3), [Cu(pzt)](n) (4), [Cu-4(pzt)(3)I](n) (5), and [Cu-7(pzt)(6)I](n) (6) were solvothermally synthesized using Hpzt (Hpzt = pyrazine-2-thiol) ligand and well-characterized by elemental analysis, infrared (IR) spectroscopy, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction (SCXRD). Six CPs exhibit either 2D (4 and 6) or 3D (1-3, and 5) network based on diverse multinuclear {CuxSy} clusters. The structural evolutions of 1-6 are greatly influenced by types of metal halides and the ligand-to-metal molar ratio used in the reaction. Among them, compound 1 displays interesting temperature-dependent photoluminescence arising from triplet cluster-centered ((CC)-C-3) excited state from the cluster metal core. Compounds 1-6 also exhibit photocurrent responses upon visible-light illumination (lambda = 420 nm) in the order 6 > 5 > 3 > 1 > 4 > 2. This work not only shows the structural diversity of {CuxSy} clusters-based CPs but also provides an interesting insight into structural modulation using crystal engineering concept.