Sythesis, Characterization And Studies On Fluorescence Property Of Rare Earth Complexes With 2-Thiopheneacetic Acid And 1,10-Phenanthrolione

Two series of twenty solid complexes of rare earth perchlorate compounds andfive different proportion co-doped complexes(Eu³⁺:La³⁺) with 2-thiophene acid and1, 10-phenanthroline have been synthesized and characterazied.Elemental analysis, rare earth coordination titration and TG-DTA studies showthat the complexes have the composition of Ln(TPAC)₃Phen (Ln³⁺=Sm³⁺,Eu³⁺,Tb³⁺,Dy³⁺); Different nuclear complexes composed of Ln_0.5RE_0.5(TPAC)₃Phen(Ln³⁺=Sm³⁺,Eu³⁺,Tb³⁺,Dy³⁺; RE³⁺=La³⁺,Gd³⁺,Y³⁺,Er³⁺); (Eu_xLa_y)(TPAC)₃Phen(x:y=0.10:0.90; 0.30:0.70; 0.40:0.60; 0.70:0.30; 0.90:0.10).The molar conductivityindicates that all the complexes are nonelectrolyte; IR spectra and ¹HNMR spectrashow that 2-thiophene acid combined as the form of chelating symmetricalbidentate ligand and phen the two nitrogen atoms are also involved in the rare earthion coordination. Fluorescence spectra and fluorescence lifetimes show that thefluorescent lifetime of single nuclear complexes are higher than different nuclear complexes, aplexes arend lifetime of a series of europium com higher than theseries of terbium; What s more,the triplet state level of the ligand is most matchingwith the excitated state level of Eu³⁺ and Tb³⁺, In addition, the influence of ligandsand co-doped ions and rare-earth ions different proportions have also beendiscussed deeply.