Photoacoustic spectroscopy study on lanthanide ternary complexes with dibenzoylmethide and phenanthroline

Abstract

The photoacoustic (PA) spectra of Eu(Dbm) 3·Phen and coprecipitates Eu 0.8Ln 0.2(Dbm) 3·Phen complexes (Ln 3+: Nd 3+, Gd 3+, Tb 3+; Dbm: dibenzoylmethide; Phen: phenanthroline) are reported. The PA intensity in the region of the ligand absorption increases for Eu 0.8Gd 0.2(Dbm) 3·Phen, Eu 0.8Tb 0.2(Dbm) 3·Phen, Eu(Dbm) 3·Phen and Eu 0.8Nd 0.2(Dbm) 3·Phen, respectively. It is indicated that additions of the second lanthanide ions change the relaxation processes of the complexes. The changes of fluorescence spectra turn out to be complementary to the PA spectra. The intramolecular energy transfer and intermolecular energy transfer processes in the coprecipitates are discussed.