Complexation, luminescence and energy transfer of Ln(III) ions with phenylphosphonic acid

Abstract Spectral characterisation of the Ln(III) ion complexes with phenylphosphonic acid (PPA) was made and the mode of Ln(III) ions coordination was established. From the absorption spectra the forces of the Nd3+ oscillator were obtained, the intensity of emission and luminescence lifetimes of Eu3+ and Tb3+ were measured. The Stern–Volmer constants K sv φ and K sv τ determined indicated the presence of associated forms of complexes. The quantum yield of luminescence of Eu3+ and Tb3+ complexes was found using Ru(bpy)32+as a standard. The complexes were characterised by quantum yields (Φ=0.4 and 0.008 for Tb and Eu ions). The solid state Eu3+ complex was studied by luminescence spectroscopy, IR and thermogravimetry. The complex was found thermally stable and with no water molecules in its structure.