Structural diversity, photoluminescence and magnet properties of complexes based on a V-shaped polycarboxylate

Abstract

The self-assembly of a V-shaped ligand 3,3′,4,4′-diphenylsulfonetetracarboxylate (dstc) and metal salts in the presence of a series of N-donor ligands yielded four new complexes, namely, [Cu4(H2dstc)4(phen)4]·12H2O (1), {[Cu2(dstc)(bpe)(H2O)2]·4H2O}n (2), [Cu3(dstc)(bipy)(μ2-OH)2(H2O)2]n (3), {[Cd5(dstc)2(bipy)2(μ3-OH)2(H2O)4]·4H2O}n (4) (phen=1,10-phenanthroline; bpe=1,2-bis(4-pyridyl)ethene; bipy=4,4′-bipyridine). All the complexes were structurally determined by single-crystal X-ray diffraction and characterized by elemental analyses, IR spectra, X-ray powder diffraction and TG analyses. Complex 1 is a discrete tetranuclear unit, which further assembles into a 3D supramolecular framework by intermolecular hydrogen bonding interactions. Complex 2 is composed of 2D 44 grid-like layers based on dinuclear copper units. Complex 3 features a rare 3D (6,8)-connected topological net consisting of trimetallic clusters. 12-connected pentanuclear cadmium clusters are observed in complex 4 and the resulting structure shows an uncommon (4,12)-connected topology. The structural differences among 1–4 demonstrate that the nature of the N-donor assistant ligands and metal ions can play critical roles in the formation and structures of the resulting complexes. Magnetic studies showed antiferromagnetic interactions for 1 and 3. In addition, the luminescent property of 4 was also studied.