Synthesis, Characterization And Studies On Fluorescence Spectra Of Coordination Compounds Of Rare Earth With P-tert-Butylcalix [8]arene

Twenty one solid coordination compounds of rare earth (Sm3+. Eu3+. Tb3+. Dy3+) and Tb3+ doped with Ln3+ (La3+ Gd3+ Y3+) with p-tert-Butyl calix[8]arene (LH8) have been synthesized and characterized. Elemental analysis, rare earth complexometry, 1HNMR spectra and TG-DTA have been studiedo The results suggest that the complexes have the composition of [RE(LH6) (N03) (DMF)3DMF. [RE2(LH2) (DMSO)5]DMSO. [RE2(LH2) (DMF)5]2DMF. Lno.5Tb0.5(LH6) (N03) (DMF)4]3DMF. [LnTb(LH2) (DMSO)5]DMSO and [LnTb(LH2) (DMF)5]2DMF respectively. The Molar conductivity indicates that all the complexes are nonelectrolyte. IR spectra show the ligand is bonded with RE (III) ion through its oxygen atom in hydroxyl group of phenol; NO3 is coordinated as a symmetrical chelating bidentate group; the coordinated atoms of DMF and DMSO are the oxygen atoms in carbonyl and sulfoxyl groups. Fluorescence spectrum suggests that the Tb3+complexes have characteristic luminescence and its fluorescence intensity is enhanced after doping with La3+, Gd3+, Y3+, influence of doping ions and neutral ligands have also been discussed. In addition, fluorescence lifetime of some complexes has been investigated. The results indicate that the variation of fluorescence lifetime coincides with its fluorescence intensity, that is to say, the stronger the fluorescence intensity, the longer the fluorescence lifetime.