Structural and spectroscopic studies of heavy lanthanide complexes with o-phenanthroline and isothiocyanate

New type of complexes [(NCS)3(o-phen)2(H2O)Ln] (Ln = Tb3+, Dy3+, Ho3+) were synthesized. The obtained results permitted us to trace the change of character of the Ln-ligand bond in the lanthanide series. The fact that lifetimes between 298 and 77 K are temperature dependent indicates the presence of the temperature dependent quenching mechanism.