Synthesis and luminescence properties of dinuclear lanthanide complexes derived from covalently linked macrocyclic ligands

A series of homo-binuclear lanthanide complexes have been prepared from DO3A derived systems containing seven-coordinate binding domains linked via an aromatic. The luminescence properties of xylyl bridged complexes show that the lanthanide ions behave as isolated centres, while the combination of the lanthanide contraction and the lipophilicity of the linker group limits inner-sphere hydration around the metal centres for later lanthanides such as ytterbium.