Photoluminescence of the europium(III) and terbium(III) homodinuclear polymeric tetraazamacrocyclic compounds

摘要

The photoluminescence properties of the new[Eu_2(16-ANE-N_4) (NO_3)(CHO_2)_3]_7 (1) and [Tb_2(16-ANE-N_4) (NO_3)(CHO_2)(CH_2O_2]_7 (2) compounds at300 and 20 K show the characteristic fluorescence spectra of theEu(III) and Tb(III) ions and an intrinsic emission when the samplesare excited at 395 and 370nm. Respectively using a xenon lamp.The observed intrinsic emission of these complexes indicates asimilar environment around the metals and evidence of the natureof these polymers. The luminescence lifetimes were found to be1.74 and 2.94 #mu#s for the ~5D_0->~7F_2 (Eu(III)) and~5D_4->~7F_5 (Tb(III)) transitions, respectively at 300K. To ourknowledge, these are the shortest lifetimes measured for Eu(III)and Tb(III) complexes so far. Both the fluorescence spectra and theluminescence lifetimes of these complexes suggest an isostructuralnature of these homodinuclear polymeric compounds.