Synthesis, Characterization and Luminescent Properties of Complexes of Rare Earth Nitrates with Tris {2-[N-(pyridine-methanoyl)amino]ethyl} amine

摘要

A tripodal ligand, tris{2-[N-(pyridine-methanoyl)amino]ethyl}amine(L), and its complexes with rare earth nitrates were synthesized. These new complexes with the general formula of Ln(NO_3)_3·L·6H_2O(where Ln = La, Nd, Eu, Tb, Y) were characterized by elemental analysis, IR spectra, thermal analysis, ~1H NMR spectra, molar conductivity and luminescent spectra. All the complexes are stable in air and their conductances in acetonitrile solution lie in the range of 142 ～ 150 S·cm~2·mol~(-1), indicating 1:1 type electrolytes. The IR and ~1H NMR spectra of the ligand and its complexes show that all the C = O groups take part in coordination to the metal ions. The thermal behaviour of Eu complex shows that the weight losses at 75 ～ 120℃ and 120 ～ 210℃ correspond to the loss of four lattice water molecules and that of two coordinated water molecules, respectively. The luminescent spectra of the complexes of Eu(Ⅲ) and Tb(Ⅲ) were investigated in methanol.