A novel homodinuclear ternary coordination polymer of nickel(II) based on two rigid ligands: Solvothermal synthesis, crystal structure, luminescent and magnetic properties

Abstract

A novel coordination polymer [Ni2(μ4-btca)(phen)2(H2O)2]n (Ni-1) was synthesized by the solvothermal reaction of nickel sulfate, 1,2,4,5-benzenetetracarboxylic acid (H4btca) and 1,10-phenanthroline (phen) in a N,N-dimethylformamide solution. The Ni(II) coordination polymer was characterized by elemental analyses, single crystal X-ray diffraction analysis, Fourier transform infrared spectroscopy, thermogravimetry and differential scanning calorimetry and fluorescence spectroscopy. The X-ray crystallographic investigation reveals that Ni(II) ion is located in N2O4 coordination spheres, and possesses an octahedron coordination environment. Ni-1 displays a neutral chain, which is built up from the Ni(II) ions bridged by the deprotonated btca4− ligands with two different coordination modes and phen is an auxiliary ligand. The result of fluorescence shows that Ni-1 has fluorescent property. Variable-temperature magnetic susceptibility study (2–300 ​K) indicates the existence of antiferromagnetic interactions in Ni-1.