Propeller‐Shaped Fe₄ and Fe₃M Molecular Nanomagnets: A Journey from Crystals to Addressable Single Molecules

Abstract

This Microreview covers the preparation and investigation of Fe 4 and Fe 3 M complexes with a propeller-like structure, most of which function as single-molecule magnets (SMMs). The magnetic characterization of these highly symmetric and chemically versatile complexes has enabled the establishment of important magneto-structural correlations regarding magnetic anisotropy and magnetic relaxation mechanisms in SMM materials. Their chemical stability and easy functionali- [a]

The Intricate Determination of Magnetic Anisotropy in Quasi-octahedral Vanadium(III): An HF-EPR and Magnetic Study

“…Previous works described several propeller-like complexes with the general formula [M 4 (L R ) 2 (dk) 6 ], in which Hdk is a β-diketone and H 3 L R is a tripodal alcohol, containing different alkyl or aryl (R) groups in the tripodal ligand [8,10,19,30]. Synthetically speaking, the nature of the R group influences the solubility of the intermediate species in the three-step procedure (see below), and of the final complex, modifying the reaction yield.…”

“…This is, however, by no means a simple task: in polynuclear clusters, it requires careful engineering of the anisotropic features of the constituent ions, the relative orientation of their magnetic anisotropy axis, and the exchange coupling among the centers [6]. In this context, one of the most accurately studied families is that of tetranuclear star-shaped complexes generally referred to as Fe 3 M′ (M′ = Fe, Cr, V, see Scheme 1) [7][8][9][10], which also proved very successful in nanostructuration processes [11][12][13].…”

Octahedral Hexachloro Environment of Dy3+ with Slow Magnetic Relaxation and Luminescent Properties

“…Since the pioneering works on [Mn 12 O 12 (CH 3 CO 2 ) 16 (H 2 O) 4 ], [1] different synthetic strategies have been elaborated to obtain compounds with efficient Single Molecule Magnet (SMM) behaviours, i. e. usable as ultra-small magnetic bit for highdensity data storage, integrated component for spintronics or Qbits for quantum applications. [2][3][4][5][6][7][8][9][10][11] The use of SMM for such applications is strongly hampered by the low temperature necessary for stabilizing the SMM state [7] as well as low chemical stability, especially when integrated onto surfaces, [12][13][14][15] or disentanglement/decoherence problem. [16][17][18][19] Many efforts have initially concerned the elaboration of molecular compounds of high nuclearity to maximize the total spin moment of the system, combined with high anisotropy barrier.…”

“…This article describes the synthesis and the characterization of the compound [BiCNIm] 3 . Several attempts to use other solvents (water or ethanol for instance) or to change the stoichiometry of the starting mixture did not lead to the title compound.…”

Combining Molecular Spintronics with Electron Paramagnetic Resonance: The Path Towards Single-Molecule Pulsed Spin Spectroscopy

“…Therefore, only a fraction of the plethora of SMM complexes [34] can eventually be integrated into spintronic devices. Promising candidates, amongst others, are TbPc 2 -based [35] and propeller-shaped Fe4/Fe 3 M-based SMMs [36]. These effects are discussed more in detail in Sect.…”