“…In one example, Mudring et al demonstrated that ILs containing the bis(trifluoromethylsulfonyl)imide (Tf 2 N À ) anion were not as ''innocent'' or ''non-coordinating'' as often presumed in the sense that they formed complexes with Yb 2+ . 61 Owing to the well-known complexation chemistry involving the b-diketonate ligand and lanthanides, 62,63 b-diketonate containing ILs are now being widely investigated for various lanthanide applications due to the favourable luminescent properties of their chelates. Since 4f-4f transitions are Laporte forbidden, direct excitation of lanthanide luminescence is not feasible.…”