A polymeric europium complex with the ligand thiophene-2-carboxylic acid: Synthesis, structural and spectroscopic characterization

作者：Cagnin Flavia; Davolos Marian R^*; Castellano Eduardo E

来源：Polyhedron, 2014, 67: 65-72.

DOI：10.1016/j.poly.2013.08.063

• Photoluminescence spectroscopy
• FTIR spectroscopy
• Thermal analysis
• X-ray diffractometry

A polymeric complex [Eu(alpha-tpc)(3)(alpha-Htpc)(2)](n) and its characterization by single crystal X-ray and thermal analysis, infrared and photoluminescence spectroscopies are described. The compound crystallizes in the monoclinic Cc space group. The asymmetric unit is formed from a europium ion bonded to one carboxyl oxygen of five different thiophene carboxylic moieties. Three of these moieties are deprotonated and bridge between neighboring europium ions giving rise to an infinite polymer along the c axis. Besides the europium characteristic emission lines, the emission spectra show unambiguously the crystal size effect on the D-5(0) -> F-7(0) transition. The complex thermal decomposition at 220 degrees C leads to a stable luminescent complex in which the D-5(0) -> F-7(4) transition reveals a monomeric characteristic. The Judd-Ofelt intensity parameters to the polymeric and the monomeric compound with the same ligand and coordination number were compared.

• 出版日期2014-1-8