Magnetic Site Dilution Approach to Achieve Bifunctional Fluorescence Thermometer and Single-Ion Magnet

In complex [Na-Dy(µ2-L)4]n(HL=8-hydroxyquinoline) (1), the DyL4 units were linked by the NaI ions to form the one-dimensional chains. The chain exhibited slow magnetic relaxation behavior at low temperature, accompanied by obvious quantum tunneling of magnetization (QTM). Very weak fluorescence was detected in 1 for the mismatching of the state energy between the DyIII and L ligand. Through magnetic dilution of diamagnetic YIII ions complex [NaDy0.02Y0.98(µ2-L)4]n (2) was obtained, in 2 the QTM of the DyIII was suppressed and single ion magnet (SIM) behavior was enhanced. More interestingly, the fluorescence emission of the 8-hydroxyquinoline was lightened by the YIII ions in 2, which intensity is linearly correlated with the temperature variation. The example of dual functional fluorescent thermometers and SIM materials are attained simply by ion dilution, achieving the effect of killing two birds with one stone.