Magnetic Relaxation Dynamics of a Binuclear Diluted Er(III)/Y(III) Compound Influenced by Lattice Solvent

It is crucial to investigate the slow relaxation mechanisms of binuclear Er^III‐based single‐molecule magnets (SMMs) and explore strategies for optimizing their magnetic properties. Herein, a doped compound, Y_1.75Er_0.25(thd)₄Pc] ? 2C₆H₆ ( YEr ? 2C₆H₆ , Hthd=2,2,6,6‐tetramethylheptanedione, H₂Pc=phthalocyanine), was synthesized by doping the paramagnetic erbium(III) compound Er₂ ? 2C₆H₆ in the diamagnetic yttrium(III) matrix Y₂ ? 2C₆H₆ . The doping effect was studied using SQUID magnetization measurements. The results suggest that magnetic‐site dilution improves the magnetic property from a fast relaxation of the pure Er^III compound to a typical SMM relaxation process of the doped sample. In this binuclear system, the dominant single‐ion relaxation is entangled with the neighboring Er^III ion through the intramolecular Er^III???Er^III interaction, which plays an important role in suppressing the quantum tunneling of the magnetization (QTM) process. Furthermore, the influence of lattice solvents on single‐ion relaxation was studied. By releasing the benzene molecules, compound YEr ? 2C₆H₆ can be successfully transformed to a desolvated sample YEr accompanied by structural alteration and improved SMM performance.