Inorganic Chemistry, Vol.37, No.6, 1401-1412, 1998
Electronic state structure and optical properties of Tb(oda)(3)(3-) complexes in trigonal Na-3[Tb(oda)(3)]center dot 2NaClO(4)center dot 6H(2)O crystals
Polarized optical absorption and emission measurements are used to locate and assign 95 crystal-field energy levels split out of the 4f(8) electronic configuration of Tb3+ in single crystals of Na-3[Tb(oda)(3)]. 2NaClO(4) . 6H(2)O (where oda denotes an oxydiacetate ligand). The absorption measurements span the 235-490 nm wavelength range, and the emission measurements span the 485-685 nm wavelength range. The combined absorption and emission spectra measurements provide access to the energy-level structures of 46 different 4f(8)[SL]J multiplet manifolds of Tb3+ (all multiplet manifolds with baricenter energies <42 400 cm(-1) above ground). The site symmetry of the Tb3+ ions in Na-3[Tb(oda)(3)]. 2NaClO(4) . 6H(2)O is D-3, and the point-group symmetry of the tristerdentate Tb(oda)(3)(3-) coordination complexes is also D-3. The Tb(oda)(3)(3-) complexes are chiral, and they exist in just one, fully resolved enantiomeric form in single crystals of Na-3[Tb(oda)(3)]. 2NaClO(4) . 6H(2)O. The crystals exhibit strong chiroptical activity in their absorption and emission spectra, and results obtained from both circularly polarized and linearly polarized optical spectra measurements are used in making transition line assignments. The energy-level data acquired from the spectroscopic measurements are analyzed in terms of a model Hamiltonian that includes consideration of both isotropic and nonisotropic 4f electron/crystal-field interactions, and the interaction parameters derived from this analysis are discussed and then compared with those obtained for other Na-3[Ln(oda)(3)]. 2NaClO(4) . 6H(2)O systems and for Tb3+ in other crystalline hosts.
Keywords:CIRCULAR-DICHROISM SPECTRA;TRANSITION LINE STRENGTHS;ENERGY-LEVEL STRUCTURE;DIPOLE INTENSITY PARAMETERS;SAMARIUM 4F->4F TRANSITIONS;RARE-EARTH CARBOXYLATES;FIELD ANALYSIS;ABSORPTION-SPECTRA;SINGLE-CRYSTAL;GADOLINIUM DIGLYCOLATE