Crystal Field Splitting of the Ground State of Terbium(III) and Dysprosium(III) Complexes with a Triimidazolyl Tripod Ligand and an Acetate Determined by Magnetic Analysis and Luminescence

The mononuclear TbIII and DyIII complexes [LnIII(H3L)(OAc)](ClO4)2·MeOH·H2O were synthesized with an N7 tripodal ligand and a bidentate acetate defining a capped-square-antiprismatic coordination geometry. The magnetic data were analyzed by a spin Hamiltonian including the crystal field on LnIII ions to give the energy diagrams of the ground states 7F6 of TbIII and 6H15/2 of DyIII. A good correlation was obtained between the energy diagrams and the fine structure in the emission spectra. ac measurements indicated field-induced SIM.