Synthesis, crystal structures, magnetic and luminescent properties of nickel(II) and cadmium(II) coordination polymers bearing 5-(2'-carboxylphenyl) nicotate ligands

摘要

Two coordination polymers, namely [M(cpna)-(phen)(H2O)]_n (M = Ni, 1; Cd, 2, H2cpna = 5-(2'-carb-oxylphenyl) nicotic acid, phen = 1,10-phenanthroline), have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction, magnetic and luminescence measurements. Single-crystal X-ray diffraction studies show that the two complexes are isostructural polymers. They have 1D step-like chain structures, which are further extended into 3D metal-organic supramolecular frameworks by π-π stacking interactions. Magnetic studies for complex 1 show antiferromagnetic coupling between the adjacent Ni(II) centers, with g = 2.10 and J = -4.30 cm~(-1). Complex 2 displays strong green fluorescent emission at room temperature.