Syntheses, crystal structures, and optical properties of five metal complexes constructed from a V-shaped thiophene-containing ligand and different dicarboxylate ligands

Abstract

Five new metal complexes, {[Ni(DIDP)(m-bdc)(H₂O)]·5H₂O}_n (1), {[Zn(DIDP)(hfipbb)]·2DMA}_n (2), {[Zn(DIDP)(4,4′-sdb)]·H₂O}_n (3), {[Co(DIDP)(p-bdc)]}_n (4), and {[Co₂(DIDP)(hfipbb)₂]·H₂O}_n (5), have been synthesized by reactions of the corresponding metal ions with a V-shaped ligand 2,8-di(1H-imidazol-1-yl)dibenzothiophene (DIDP) and different aromatic dicarboxylic acids, namely isophthalic acid (m-H₂bdc), terephthalic acid (p-H₂bdc), 4,4′-(hexafluoroisopropylidene)bis(benzoic acid) (H₂hfipbb), and 4,4′-sulfonyldicarboxylic acid (4,4′-H₂sdb), respectively. The structures of the complexes were determined by X-ray single-crystal diffraction. Complex 1 is a 1D chain structure containing a one-dimensional channel along the a direction and is further extended via O–H⋯S hydrogen bonds and C–H⋯π stacking interactions into a 3D framework. Complex 2 exhibits a quasi 2D + 2D → 2D with parallel polycatenation of 2D (4, 4) nets. Complex 3 displays an unusual 2D + 2D → 3D parallel polycatenated framework based on a 2D 6³-hcb network. Complex 4 shows a 2D 4-connected {4⁴·6²}-sql network containing a one-dimensional channel along the b direction. The adjacent 2D networks are further extended via C–H⋯O hydrogen bonds into a 3D supramolecular framework. Complex 5 features a 2-fold interpenetrating 3D framework with a 6-connected {4¹²·6³} pcu topology. Furthermore, the thermal stability for 1–5 and luminescence properties of 2 and 3 have been studied. Moreover, the solid-state UV-visible spectroscopy experiments show that complexes 1–5 are all optical semiconductors with band gaps of 3.06, 3.18, 3.23, 2.98, and 3.17 eV, respectively.