Comparison of optical properties of tris(4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedionato)europium(III) single crystals with dipyridyl and phenanthroline

The aim of this work is comparison of the spectroscopic behaviour of two europium compounds with the formula Eu(TAN)3dipy (1) and Eu(TAN)3phen (2) where TAN = 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedionate, dipy = 2,2′dipyridine and phen = 1,10 phenathroline). The synthesized single crystals of the complexes were investigated by the high-resolution photoluminescence spectroscopy both at room and low temperature as well as by the decay times measurements. Both compounds show a very strong red emission after excitation in the UV range of the ligand absorption band. The dynamic of the excited state will be discussed. The paths of energy transfer are analyzed and mechanism of this process will be proposed. The influence of dipyridyl/phenanthroline, the Lewis base second ligand, on spectroscopic characteristic will be displayed.