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The overall quantum yields for phenanthridinium sensitised emission from a europium ion have been measured in H₂O and D₂O for a series of five structurally related, octadentate ligands in which the distance from the phenanthridinium chromophore to the Eu ion varies from 2.5 to ca. 8.2 Å. Overall quantum yields (pD2) range from 0.25 to 0.012 suggesting that the experimental distance for 50% efficiency of intramolecular energy transfer lies close to 5.5 Åfor this system.

The C₄-symmetric (S )-tetra(4-quinolyl) tetraamide derivative of dota has been prepared. The sodium complex has been characterised by X-ray crystallography and although the quinolyl groups are appropriately oriented for exciton coupling in the solid-state, in solution no evidence for coupling was found for the free ligand nor its protonated, Na, Ca or Eu complexes. Instead, excimer formation was observed in emission consistent with a coplanar arrangement of the quinolyl groups.

A palladium porphyrin has been covalently linked to a chiral lanthanide complex and effectively sensitises near-IR emission from Nd and Yb; sensitisation is enhanced in the absence of oxygen and in the presence of a nucleic acid.

Metal- and ligand-based luminescence, absorption and circular dichroism difference spectroscopy signal the extent and nature of binding of enantiopure Δ and Λ cationic lanthanide complexes to [(CG)₆]₂ and [(AT)₆]₂.