Spectroscopy of related series of Eu and Tb carboxylates

A critical review of the recent works of author and his colleagues on spectroscopy of related series of europium and terbium pyridine-carboxylates and pyridine-dicarboxylates is undertaken. Luminescence, luminescence excitation, IR, Raman, and vibronic spectra of these compounds were discussed. Studies of spectra of the complex lanthanide nitrates with sulfoxides were reviewed also. Intraligand charge transfer (CT) bands in the luminescence excitation spectra were demonstrated by comparison of the spectra of europium and terbium salts. f–d transitions in spectra of some terbium salts were revealed also. A series of complex terbium salts with increasing donor–acceptor interaction of the metal cation and ligand’s nitrogen was forecasted. Comparison of the spectra of pyridine-carboxylate and pyridine-dicarboxylate shed light on the coordination function of the carboxylate groups and on the nature of the ligand-to-metal-ion charge transfer (LMCT) in the lanthanide pyridine-dicarboxylates. The influence of the introduction of spacers in the system of conjugated π-orbitals of the ligands on the rate of the energy transfer to the lanthanide cation was demonstrated also.