Synthesis, Crystal Structure, Luminescence Sensing of a Zn(II) Coordination Polymer Based on 2,5-Dihydroxyterephthalic Acid and 2,2'-Bipyridine

Abstract: A new coordination polymer, namely, [Zn(Bpy)(DHTA)0.5]n (DHTA = 2,5-dihydroxy-1,4-terephthalic acid tetra-anion, Bpy = 2,2'-bipyridine) has been synthesized under hydrothermal conditions. The structure has been determined by single crystal X-ray diffraction, thermal gravimetric analysis, infrared spectrum and luminescent properties. The [Zn(Bpy)(DHTA)0.5]n contains one Zn(II), the metal center Zn(II) is five-coordinated. Complex 1 was stable up to 380 oC, and a sharp weight loss in the temperature range 380-570 oC was observed, the residual is zinc(II) oxide (ZnO). The complex 1 exhibits an emission at 365 nm (λex = 316 nm). The photoluminescence results suggest that complex 1 has potential as a new luminescence material. The quantum chemistry calculations results indicate that the atomic net charge distribution in the complex 1 shows obvious covalent interactions between the coordinated atoms and Zn(II) ion. Meanwhile, the ΔE (ELUMO - EHOMO) value to be - 0.096 a.u. The luminescence explorations demonstrated that complex 1 exhibits highly selective and sensitive sensing for organic solvents (DMK) and metal ion (Fe3+).