Dynamic Magnetic and Optical Insight into a High Performance Pentagonal Bipyramidal DyIII Single-Ion Magnet

The pentagonal bipyramidal single-ion magnets (SIMs) are among the most attractive prototypes of high-performance single-molecule magnets (SMMs). Here, a fluorescence-active phosphine oxide ligand CyPh2PO (=cyclohexyl(diphenyl)phosphine oxide) was introduced into [Dy(CyPh2PO)(2)(H2O)(5)]Br(3)2(CyPh2PO)EtOH3H(2)O, and combined dynamic magnetic measurement, optical characterization, ab initio calculation, and magneto-optical correlation of this high-performance pseudo-D-5h Dy-III SIM with large U-eff (508(2)K) and high magnetic hysteresis temperature (19K) were performed. This work provides a deeper insight into the rational design of promising molecular magnets.