Helicenic Complexes of Lanthanides: Influence of the f‐Element on the Intersystem Crossing Efficiency and Competition between Luminescence and Oxygen Sensitization

The coordination of a helicene-functionalized bipyridine to various lanthanide complexes (Ln = Y, Eu, Yb, Gd) led to the formation of an isostructural series. The photophysical study indicated that non-emissive lanthanides act as heavy atoms strongly enhancing singlet oxygen generation. We also demonstrated that sensitization of the f-f luminescence is in competition with singlet oxygen generation.