A Dysprosium Metallocene Single‐Molecule Magnet Functioning at the Axial Limit

Abstract

Abstraction of a chloride ligand from the dysprosium metallocene [(Cpttt)2DyCl] (1Dy Cpttt=1,2,4‐tri(tert‐butyl)cyclopentadienide) by the triethylsilylium cation produces the first base‐free rare‐earth metallocenium cation [(Cpttt)2Dy]+ (2Dy) as a salt of the non‐coordinating [B(C6F5)4]− anion. Magnetic measurements reveal that [2Dy][B(C6F5)4] is an SMM with a record anisotropy barrier up to 1277 cm−1 (1837 K) in zero field and a record magnetic blocking temperature of 60 K, including hysteresis with coercivity. The exceptional magnetic axiality of 2Dy is further highlighted by computational studies, which reveal this system to be the first lanthanide SMM in which all low‐lying Kramers doublets correspond to a well‐defined MJ value, with no significant mixing even in the higher doublets.

Tetrathiafulvalene-Based Magnets of Lanthanides

“…It is the opposite for the prolate Yb(III) for which the negative charges must lie in the xy plane. This textbook analysis guided the synthesis of the most efficient SMM reported so far [3,4]. Additionally, advanced quantum calculations have demonstrated that such approach might provide high-temperature SMMs (if chemically accessible) [43,44].…”

“…The first example we want to introduce is based on a similar TTF ligand with a benzothiazole group. The ligand L 3 (Fig. 9) with a square antiprismatic idealized coordination polyhedron.…”

A tunable lanthanide cubane platform incorporating air-stable radical ligands for enhanced magnetic communication

“…The recent shift towards 4f ions in the field of molecular magnetism, however, has yielded impressive growth in mononuclear and dinuclear SMMs; largely due to the inherent magnetic anisotropy of the lanthanide elements [12][13][14][15] . Recently, our research efforts in the development of dinuclear SMMs stem from a desire to understand and overcome the challenges related to the magnetic coupling of core 4f orbitals 16,17 .…”

Assembling High-Temperature Single-Molecule Magnets with Low-Coordinate Bis(amido) Dysprosium Unit [DyN 2 ] + via Cl–K–Cl Linkage

“…[10][11][12][13][14][15][16][17][18][19] Using the principle of the electronic density match between the 4f orbitals and the coordinate ligands, [20][21][22] several remarkable single-ion magnets (SIMs), mainly based on oblate Dy 3+ ion [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41] and prolate Er 3+ ion, [42][43][44][45] were built. The astonishing finding of dysprosium(III) (Dy III ) metallocene SMMs, [36][37][38][39][40][41] especially [(Cp iPr5 )Dy(Cp*)] + , 40 which exhibited hysteresis opening temperature of 80 K (above the liquid nitrogen region; U eff = 2217 K), further demonstrated the enormous potential of Ln-SMMs. Besides, a series of D 5h and D 6h symmetric SMMs with a considerable energy barrier up to 1815 K have been reported, [24][25]…”