Hydrothermal syntheses and characterization of four 2-D lanthanide coordination polymers with glutarate and 1,10-phenanthroline

Abstract

Four 2-D coordination polymers Ln₂(phen)₂(C₅H₆O₄)₃ [Ln = Pr(1), Eu(2), Er(3), Yb(4), phen = 1,10-phenanthroline] were obtained via hydrothermal reactions and determined by X-ray diffraction analysis. The crystal structure data reveal that these complexes are isostructural. In the asymmetric unit, the two Ln(III) ions are nine-coordinate and have similar coordination environments. The Ln(III) ions are built into 2-D layers by three different coordination modes of glutarate. The resulting 2-D layer forms 3-D supramolecular architecture by two types of π···π stacking interactions. All the complexes were characterized by IR spectra and thermogravimetric analysis, and the emission spectrum shows that Eu₂(phen)₂(C₅H₆O₄)₃ possesses strong luminescence.

Keywords:

• Lanthanide coordination polymer
• Crystal structure
• Luminescence
• Glutarate

Acknowledgments

This project was sponsored by the K.C. Wong Magna Fund at Ningbo University and the Ningbo Municipal Natural Science Foundation grant no. (2010A610160) and the Subject Object no. (xk1070) at Ningbo University.