Systematic study of luminescent properties of new lanthanide complexes using crown ethers as ligand

► Lanthanide-crown ethers complexes were synthesized and characterized. ► The polarizability's effect of the ligands was verified from the emission spectra. ► The Eu-15C5-phen complex showed the highest quantum efficiency (71.6%). ► All complexes showed high efficiency in spite of ethers doesn't act as good antenna.