Synthesis, X-ray structure and luminescent properties of a new 1D terbium(III) coordination polymer based on 2,4-dichlorophenoxyacetate and 4,4′-bipyridine

Abstract

A new 1D terbium coordination polymer, {[Tb(2,4-dcpa)3(H2O)2]·(4,4′-bpy)1.5(H2O)2}n (1) [2,4,-dcpa=2,4-dichlorophenoxyacetate, 4,4′-bpy=4,4′-bipyridine], was prepared by hydrothermal synthesis and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. Complex 1 exhibits an infinite chain structure with a {Tb2(2,4-dcpa)6(H2O)4} dimeric repeat unit. Each Tb3+ ion is nine-coordinated to two water molecules, one monodentate carboxylate group and four bridging carboxylate groups in which the carboxylate groups are bonded to the terbium ion in one modes: the chelating–bridging tridentate. Three-dimensional fluorescence spectra of 1 were detected at room temperature under the excitation and the emission wavelengths in the range of 420–750nm with the interval of 5nm. The lifetime of 1 in solid-state at room temperature up to 1.132ms. On the other hand, poor luminescence efficiency has been noted for the Tb3+-2,4-dcpa complex.