Seven-Coordinate Tb Complexes with 90% Quantum Yields: High-Performance Examples of Combined Singlet- and Triplet-to-Tb Energy-Transfer Pathways.

Seven-coordinate, pentagonal-bipyramidal (PBP) complexes [Ln(bbpen)Cl] and [Ln(bbppn)Cl], in which Ln = Tb (products and ), Eu ( and ), and Gd ( and ), with bbpen = ,'-bis(2-oxidobenzyl)-,'-bis(pyridin-2-ylmethyl)ethylenediamine and bbppn = ,'-bis(2-oxidobenzyl)-,'-bis(pyridin-2-ylmethyl)-1,2-propanediamine, were synthesized and characterized by single-crystal X-ray diffraction analysis, alternating-current magnetic susceptibility measurements, and photoluminescence (steady-state and time-resolved) spectroscopy. Under a static magnetic field of 0.1 T, the Tb complexes and revealed single-ion-magnet behavior.

Promoting a Significant Increase in the Photoluminescence Quantum Yield of Terbium(III) Complexes by Ligand Modification.

Two discrete mononuclear complexes, [Tb(bbpen)(NO)] () and [Tb(bbppn)(NO)] (), for which = -bis(2-hydroxybenzyl)--bis(pyridin-2-ylmethyl)ethylenediamine and = bis(2-hydroxylbenzyl)-bis(pyridin-2-ylmethyl)-1,2-propanediamine, were synthesized and characterized by FTIR, Raman, and photoluminescence (PL, steady-state and time-resolved modes) spectroscopy. The attachment of a methyl group to the ethylenediamine portion of the ligand backbone differentiates from and acts as a determining feature to both the structural and optical properties of the former. The single-crystal X-ray structure of is described here for the first time, while that of complex has been redetermined in the monoclinic 2 space group in light of new diffraction data.