The SMM properties of the spatially closed Dy(Ⅲ) double-decker Pc complex Dy(obPc)2 (1), which is equivalent to a pseudo dinuclear complex, are reported. Complex 1 crystallized with ethanol in the crystal latti...The SMM properties of the spatially closed Dy(Ⅲ) double-decker Pc complex Dy(obPc)2 (1), which is equivalent to a pseudo dinuclear complex, are reported. Complex 1 crystallized with ethanol in the crystal lattice in the monoclinic space group P22/n and was isomorphous with Tb(obPc)2 (3), which is arranged in a dimer structure along the b axis. The intermetallic Dy-Dy distance was determined to be 0.756 nm. ZMT versus T plots for 1 decreased with a decrease in T, which suggests the existence of an antiferromagnetic (AF) interaction between the Dy3+ ions. The M-H curve for 1 at 1.8 K showed magnetic hysteresis. In ac susceptibility measurements on a powder sample of 1, which were dependent on the applied ac field, indicating that 1 is an single molecule magnet (SMM), a maximum appeared at 22 K at an ac frequency 09 of 1488 Hz. The shape of the peaks dras- tically changed, and the peaks did not shift when an Hd~ large enough to suppress the quantum tunneling of the magnetization (QTM) was applied. The energy barrier (A/hc) was estimated to be 44 cm-1 with a pre-exponential factor (r0) of 1.6 × 10-5 s from an Arrhenius plot. Our results suggest that the SMM/magnetic properties of 1 significantly change in a dc magnetic field. These relaxation mechanisms are related to the energy gap of the ground state and to QTM.展开更多
基金financially supported by a Grant-in-Aid for Scientific Research(s) (20225003) from the Ministry of Education, Culture, Sports,Science, and Technology, Japan
文摘The SMM properties of the spatially closed Dy(Ⅲ) double-decker Pc complex Dy(obPc)2 (1), which is equivalent to a pseudo dinuclear complex, are reported. Complex 1 crystallized with ethanol in the crystal lattice in the monoclinic space group P22/n and was isomorphous with Tb(obPc)2 (3), which is arranged in a dimer structure along the b axis. The intermetallic Dy-Dy distance was determined to be 0.756 nm. ZMT versus T plots for 1 decreased with a decrease in T, which suggests the existence of an antiferromagnetic (AF) interaction between the Dy3+ ions. The M-H curve for 1 at 1.8 K showed magnetic hysteresis. In ac susceptibility measurements on a powder sample of 1, which were dependent on the applied ac field, indicating that 1 is an single molecule magnet (SMM), a maximum appeared at 22 K at an ac frequency 09 of 1488 Hz. The shape of the peaks dras- tically changed, and the peaks did not shift when an Hd~ large enough to suppress the quantum tunneling of the magnetization (QTM) was applied. The energy barrier (A/hc) was estimated to be 44 cm-1 with a pre-exponential factor (r0) of 1.6 × 10-5 s from an Arrhenius plot. Our results suggest that the SMM/magnetic properties of 1 significantly change in a dc magnetic field. These relaxation mechanisms are related to the energy gap of the ground state and to QTM.