Mono- and heterometallic europium (III) and terbium (III) complexes: Synthesis, crystal structures and luminescent properties

摘要

Four new rare earth organometallic coordination polymers [Eu-III(Hbidc)(pdc)center dot 2(H2O](2)center dot 4H(2)O (1), [Tb-(III)(Hbidc)(pdc)center dot 2(H2O)](2) (2), and {[Ln(III)Ag(I)(bidc)(pdc)center dot 2(H2O)]}(n)center dot H2O (Ln = Eu (3), Tb (4)) (H(2)bidc = 1H-benzimidazole-5,6-dicarboxylic acid, H(2)pdc = 2,6-pyridine dicarboxylic acid) have been synthesized through self-assembly reactions. The X-ray single crystal diffraction indicates that these complexes are isomorphous, namely triclinic P - 1. Interlayer O-H center dot center dot center dot O and C-H center dot center dot center dot O hydrogen bonding has been observed in the structure of four complexes, generating 1D zigzag infinite chain, 2D plane layer, and even 3D ladder-like supramolecular framework. Addition of silver nitrate to chemicals leads to massive restructuring and emission intensity enhancement of complexes 3 and 4. Furthermore, thermal stabilities and luminescent of 1-4 have also been discussed in detail. (C) 2015 Elsevier B.V. All rights reserved.