A luminescence quantum yield of 7.8% was obtained for a quaternary mixed-ligand samarium complex; this value is higher than those previously reported in the literature for such complexes in solution. The complex was prepared by microwave-assisted synthesis in 15 min with a yield of 69%; that is, ∼400 times faster than the usual synthesis that required 4 days and led to a yield of only 30%. Therefore, we propose microwave-assisted synthesis as the method of choice for preparing mixed-ligand lanthanoid complexes.

By combining NMR data (nuclear Overhauser effect and pseudocontact shifts) with luminescence measurements, we uncover how the structure of an anionic europium complex adapts to different solvent polarities as a...