Ultrahard magnetism from mixed-valence dilanthanide complexes with metal-metal bonding

Abstract

Magnetic effects of lanthanide bonding Lanthanide coordination compounds have attracted attention for their persistent magnetic properties near liquid nitrogen temperature, well above alternative molecular magnets. Gould et al . report that introducing metal-metal bonding can enhance coercivity. Reduction of iodide-bridged terbium or dysprosium dimers resulted in a single electron bond between the metals, which enforced alignment of the other valence electrons. The resultant coercive fields exceeded 14 tesla below 50 and 60 kelvin for the terbium and dysprosium compounds, respectively. —JSY

Understanding the magnetic anisotropy for linear sandwich [Er(COT)]+-based compounds: a theoretical investigation

“…7–9 Layfield et al reported a dysprosium metallocene cation [(Cp iPr5 )Dy(Cp*)] + showing an exceptionally high anisotropy barrier U eff of 1541 cm −1 , and its 100 s blocking temperature T B is 65 K. 10 In 2022, Long, et al just reported one dilanthanide complex with metal–metal bonding whose energy barrier and blocking temperature are up to 1631 cm −1 and 72 K, respectively. 11 Recently, we also theoretically predicted that the energy barrier and blocking temperature of one two-coordinate [Co(C(SiMe 2 ONaphthyl) 3 ) 2 ] 12 can be enhanced up to 1559.1 cm −1 and 90 K, respectively, through the structural distortion. 13 To date, a lot of high-performance SIMs with high energy barriers and blocking temperatures are almost Dy III -based complexes.…”

Lanthanide-mediated tuning of electronic and magnetic properties in heterotrimetallic cyclooctatetraenyl multidecker self-assemblies

“…[1][2][3][4] This attention is not surprising, given the near-innite number of possible combinations of metals, ligands, and their spatial-orientations. It is precisely this diversity of constitutional and structural possibilities that has given rise to a wide range of physical properties and applications such as single-molecule magnets (SMMs), [5][6][7][8][9] luminescence, 10,11 and catalysis. 12,13 Importantly, with powerful design concepts, the properties of individual metal centers can be modulated through variations of experimental conditions and the structural environment, [14][15][16] thus entailing novel responsive compounds, which exhibit properties superior in complexity to their homometallic analogues and lower-nuclearity cognates.…”

Spin-Phonon Relaxation in Magnetic Molecules: Theory, Predictions and Insights

“…These findings have major consequences for molecular magnetism practices. In addition to well established approaches to increase the axiality of the crystal field [102] and exchange coupling multiple ions [117], ab initio spin dynamics results point to the design of rigid molecular structures as key to reduce spin-phonon relaxation rates [71]. Indeed, by increasing molecular rigidity, optical modes are shifted up in energy with a two-fold effect: i) they become less admixed with acoustic modes [55], so reducing the rate of direct relaxation, and ii) they become less populated so that Raman relaxation rate would also slow down [56,57,107].…”