Intermolecular Energy Transfer Between Lanthanide Complex Ions in Micellar Solution

Two different procedures for the study of the quenching of excited states by lanthanide complex ions on the surface of micelles are considered. In the first, excited Tb(pdc)$\text{}_{3}^{3-}$ (pdc = pyridine 2,6-dicarboxylate) complex ions are held in close proximity to other Ln(pdc)$\text{}_{3}^{3-}$ ions on the surface of cetyl trimethyl ammonium micelles. Efficient energy transfer is observed by the electric dipole-electric dipole mechanism with a mean interaction distance only slightly greater than that which exists in the crystalline complexes. In the second, the excited state of Tb(pdc)$\text{}_{3}^{3-}$ is depopulated by energy transfer to the coexcited lowest excited triplet state of phenanthrene which is thereby excited to the second triplet state.