Optical activity in mixed-ligand terbium complexes containing 1,2-Benzenedicarboxylic acid and chiral carboxylic acids

The optical activity of Tb(PHT)(L) complexes has been studied by means of circularly polarized luminescence (CPL) spectroscopy, where PHT=1,2-benzenedicarboxylic acid (phthalic acid) and L=L-mandelic, L-aspartic, and L-malic acids. The CPL spectra were characteristic of multidentate bonding, and close examination of the spectra revealed the nature of the metal-ligand bonding. The results obtained have demonstrated that the optical activity experienced by the Tb(III) ion is primarily determined by the nature of the chiral ligand, and that this chirality can be affected by the achiral ligands also bound in the metal coordination sphere.