Lanthanide Single‐molecule Magnets: Synthetic Strategy, Structures, Properties and Recent Advances

Abstract

Single-molecule magnets (SMMs) show wide potential applications in the field of ultrahigh-density storage materials, quantum computing, spintronics, and so on. Lanthanide (Ln) SMMs, as an important category of SMMs, open up a promising prospect due to their large magnetic moments and huge magnetic anisotropy. However, the construction of high performance for Ln SMMs remains an enormous challenge. Although remarkable advances are focused on the topic of Ln SMMs, the research on Ln SMMs with different nuclear numbers is still deficient. Therefore, this review summarizes the design strategies for the con-struction of Ln SMMs, as well as the metal skeleton types. Furthermore, we collect reported Ln SMMs with mononuclearity, dinuclearity, and multinuclearity (three or more Ln spin centers) and the SMM properties including energy barrier (U eff ) and pre-exponential factor (τ 0 ) are described. Finally, Ln SMMs with low-nuclearity SMMs, especially for single-ion magnets (SIMs), are highlighted to understand the correlations between structures and magnetic behavior of the detail SMM properties are described. We expect the review can shed light on the future developments of highperformance Ln SMMs.

Lanthanide Complexes with Tripodal Ligands

“…Therefore, the analysis of currently known molecular mononuclear complexes containing tripodal ter-and tetradentate ligands is aimed at drawing the attention of the scientific community to the use of such ligands in the design of Ln complexes with uniaxial anisotropy. To date, approaches have been developed to choice the most suitable Ln-ion for the appropriate ligand environment, based on the shape of 4f-electron clouds (oblate or prolate) for both the ground state and the excited levels of the central atom [60,[76][77][78].…”

The Tripodal Ligand’s 4f Complexes: Use in Molecular Magnetism

“…Therefore, the analysis of currently known molecular mononuclear complexes containing tripodal ter-and tetradentate ligands is aimed at drawing the attention of the scientific community to the use of such ligands in the design of Ln complexes with uniaxial anisotropy. To date, approaches based on the shape of 4f electron clouds (oblate or prolate) have been developed to select the most suitable Ln-ions for an appropriate ligand field for both the ground state and the excited levels of the central atom [60,[76][77][78]. The first and most studied coordinative tripods were the scorpionate ligands, hydrotris(pyrazolyl)borates, first obtained by S. Trofimenko [33,35].…”

Modulation of the Slow Relaxation of the Magnetization Dynamics through Second Coordination Sphere in Macrocyclic Dysprosium(III) Complexes

“…These molecular systems hold great potential for future applications in high-density data storage or quantum computing. − Lanthanide ions, with their high magnetic anisotropy, have played a transformative role in this field over the last two decades. Maximizing the magnetic anisotropy in these systems requires the fine-tuning of the coordination environment to enhance crystal-field (CF) splitting, creating anisotropic barriers for magnetization reversal. ,− …”

“…Comparative analysis of the molecular structures of complexes 1 and 2 highlights noticeable differences in the arrangement of the hexadentate macrocyclic ligand. In complex 1, the macrocycle exhibits a severe bending with respect to 2, as evidenced from the N pyr −Dy−N pyr angle value, which is 154.44 (7) using SHAPE software, 46 which indicates that the geometry of the macrocycle in complex 2 is closer to a hexagon (SHAPE values of 2.598 vs 3.056 for 1, Table S1). Additionally, the decacoordinated geometry obtained by SHAPE in complex 2 (2.147) is closer to an ideal arrangement when compared to complex 1 (2.560, Table S2).…”