Magnetic hysteresis and large coercivity in bisbenzimidazole radical-bridged dilanthanide complexes

Abstract

Unprecedented bisbenzimidazole (Bbim)3−˙ radical-bridged dilanthanide complexes were isolated where the dysprosium congener features magnetic memory effect and the second highest coercive field for any organic radical-bridged dinuclear compound.

Pyrrolyl-Bridged Metallocene Complexes: From Synthesis, Electronic Structure, to Single-Molecule Magnetism

“…The reduced magnetization ( H / T vs M ) does not overlap (Figure S33), indicative of significant magnetic anisotropy and/or low-lying excited states . Organometallic dysprosium chemistry paved the way for various advances at the forefront of SMM design. ,, When used in conjunction with a strong, axial crystal field, the Dy III ion can display features of SMM behavior . An alternative approach is to induce strong magnetic exchange coupling through the implementation of metal–metal bonds, radical bridging ligands, or diamagnetic bridging ligands with diffuse orbitals capable of penetrating the 4 f -shell.…”

Dipolar Coupling as a Mechanism for Fine Control of Magnetic States in ErCOT-Alkyl Molecular Magnets

“…While SIMs have pushed the boundaries of controlling spin–lattice relaxation out to technologically relevant temperatures, many quantum technologies require arrays of multiple coupled spins; − such coupling strategies work to enhance SMM relaxation behavior by affecting QTM at zero and applied fields as well. , Several examples exist of molecular systems with exceptional hysteretic behavior and an effective quenching of QTM by coupling highly anisotropic magnetic states, either directly or through a molecular bridge bearing spin density, to yield highly anisotropic “giant spins” akin to the clusters that established SMMs. − One route to building higher nuclearity molecular magnets is that of the “building block” approach, wherein several magnetic units with well-defined and synthetically robust ground states are linked to build systems with conserved anisotropy. − However, compatibility with open-shell bridges is difficult due to the charge-dense and highly penetrating radicals either destroying the anisotropy enforced by the comparatively weak crystal field or introducing large coupling so that magnetic energy levels become close and can easily mix.…”

Ab initio-based determination of lanthanoid–radical exchange as visualised by inelastic neutron scattering

“…18 The overall magnetic moment of the complex can also be increased by coupling multiple spins into a “giant spin”, which while a common approach for TM-SMMs, 19 has not been as widely used for Ln-SMMs, due to their typically weaker magnetic exchange coupling. 13,20–23…”