Photophysical studies of europium coordination polymers based on a tetracarboxylate ligand

Inorg Chem. 2013 Jul 1;52(13):7658-65. doi: 10.1021/ic400777c. Epub 2013 Jun 17.

Abstract

Reaction of europium sulfate octahydrate with p-terphenyl-3,3″,5,5″-tetracarboxylic acid (H4ptptc) in a mixed solvent system has afforded three new coordination polymers formulated as {[Eu(ptptc)0.75(H2O)2]·0.5DMF·1.5H2O}n (1), {[Me2H2N]2 [Eu2(ptptc)2(H2O)(DMF)]·1.5DMF·7H2O}n (2), and {[Eu(Hptptc)(H2O)4]·0.5DMF·H2O}n (3). Complex 1 exhibits a three-dimensional (3D) metal-organic framework based on {Eu2(μ2-COO)2(COO)4}n chains, complex 2 shows a 3D metal-organic framework constructed by [Eu2(μ2-COO)2(COO)6](2-) dimetallic subunits, and complex 3 features a 2D layer architecture assembling to 3D framework through π···π interactions. All complexes exhibit the characteristic red luminescence of Eu(III) ion. The triplet state of ligand H4ptptc matches well with the emission level of Eu(III) ion, which allows the preparation of new optical materials with enhanced luminescence properties. The luminescence properties of these complexes are further studied in terms of their emission quantum yields, emission lifetimes, and the radiative/nonradiative rates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carboxylic Acids / chemistry*
  • Coordination Complexes / chemistry*
  • Europium / chemistry*
  • Luminescence
  • Models, Molecular
  • Polymers / chemistry*

Substances

  • Carboxylic Acids
  • Coordination Complexes
  • Polymers
  • Europium