Structural and spectroscopic studies of lanthanide complexes with S(+)-mandelic acid

Lanthanide (Gd3+, Tb3+, Dy3+, Er3+) complexes with S(+)-mandelic acid were synthesized in the form of powders and were characterized by elemental and thermal analyses, XRPD method, FTIR, Raman and UV–vis–NIR spectroscopy. It was found that all the complexes were isostructural with the erbium R(−)mandelate, Er(Man)3(H2O)2, for which the crystal structure was previously determined. Photophysical studies carried out on the solid samples have revealed that the mandelate ligand is a better sensitizer for Tb3+ than Dy3+ ion. The luminescence quantum yields of these compounds were estimated as 95% and 6%, respectively.

► Synthesis of terbium and dysprosium mandelates in the form of powders.
► Structural studies.
► UV–vis–NIR-IR measurements.
► Photophysical properties.
► Mandelate ligand as an effective sensitizer for Tb3+ and Dy3+ ions.