Rigid Dysprosium(III) Single‐Molecule Magnets Exhibit Preserved Superparamagnetism in Solution

Abstract

Molecules with long preserved magnetic moments are perceived as the smallest units for storing bytes, which could bring a new revolution for information technology. However, the rational design of such molecules remains challenging. Here two rigid adamantanol ligand based dysprosium(III) complexes ([Dy(1-AdO) 2 (py) 5 ]BPh 4 -1 and [Dy(2-AdO) 2 (py) 5 ]BPh 4 -2) with pentagonal-bipyramidal coordination geometry and local D 5h symmetry were successfully prepared, which display excellent single-molecule magnet (SMM) behavior (U eff ≈ 1835 K, T B ZFC ≈ 24 K, T B 100s ≈ 17 K and T B H = 23 K for 1; U eff ≈ 1756 K, T B ZFC ≈ 20 K, T B 100s ≈ 16 K and T B H = 23 K for 2) due to the much weakened vibration in low energy regimes.Remarkably, the large energy barriers and high blocking temperatures for these two complexes in solid states are well preserved in solution. This is never observed in previous studies of SMMs, indicating that the adamantanol is rigid and can be introduced to make the composed molecules stable enough to maintain the solid state magnetic property in solution.

Double butterfly-shaped octanuclear dysprosium clusters: structure, magnetism and assembly mechanism

“…8–11 In recent years, great progress has been made in mononuclear dysprosium complex based single-molecule magnets (SMMs) with a large flip energy barrier ( U eff ) and high hysteresis temperature ( T B ). 12–18 Mononuclear dysprosium complexes may represent the lower size limit of molecule based magnetic information storage materials, which may mean that high-nucleation dysprosium clusters can comprise SMMs with better performance. Therefore, high-nuclear dysprosium based SMMs will be a more promising direction in the field of molecular magnetism in the future.…”

Manipulating Solvothermal Coordination-Catalyzed In Situ Tandem Reactions to Construct Dysprosium-Based Complexes with Different Shapes and Zero-Field SMM Behaviors

“…So far, solvothermal black-box reactions are among the most widely used methods for the synthesis of lanthanide multinuclear clusters; however, in this process, organic ligands participate only in coordination to form complexes. − The selection of suitable organic ligands with active functional groups is the premise of coordination-driven in situ tandem reactions. ,, The study of lanthanide complexes has been favored by chemists due to their applications in luminescence, magnetism, catalysis, and separation. − Dy­(III) ions possess Ising-type magnetic anisotropy originating from the Kramer double ground state and are preferred components for building single-molecule magnets (SMMs), which have important significance and potential applications in the fields of density data storage, molecular spintronics, and quantum computing. − After years of exploration, many mononuclear Dy-based SMMs with excellent blocking temperatures and energy barriers have emerged. − For example, in 2018, Tong’s group realized the key parameters for regulating the mononuclear dysprosium complexes through the design of ligands and obtained the axial crystal field, and finally achieved the first breakthrough with a T B temperature of 80 K and U eff as high as 2217 K . In 2016, Zheng’s group reported that a Dy-based SMM was obtained by adjusting the coordination environment, with a U eff = 1815 K and a T B of 14 K .…”

Syntheses, structures, and magnetic properties of acetate-bridged lanthanide complexes based on a tripodal oxygen ligand

“…So far, many high-performance mononuclear lanthanide-based SMMs, also named single-ion magnets (SIMs), have been reported ( Liu et al, 2018 ; Zhu et al, 2019 ; Parmar et al, 2021 ; Sutter et al, 2022 ). The studies revealed that a suitable crystal-field environment with specific symmetry around lanthanide spin centers, such as D 4d ( Ishikawa et al, 2003 ; Bala et al, 2019 ; Zhuo et al, 2021 ), D 4h ( Ding et al, 2021 ; Thomas-Hargreaves et al, 2021 ), D 5h ( Chen et al, 2016 ; Ding et al, 2022 ; Sutter et al, 2022 ), D 6h ( Canaj et al, 2019 ; Li et al, 2019 ; Zhu et al, 2021 ), and C ∞ ( Goodwin et al, 2017 ; Guo et al, 2017 ; Guo et al, 2018 ), usually leads to a remarkable single-ion magnetic anisotropy and slow magnetic relaxation behavior.…”