ChemInform Abstract: Mononuclear Lanthanide Single Molecule Magnets Based on the Polyoxometalates [Ln(W₅O₁₈)₂]^19‐ and [Ln(β₂‐SiW₁₁O₃₉)₂] ^13‐ (Ln^III: Tb, Dy, Ho, Er, Tm, and Yb).

Abstract

III : Tb, Dy, Ho, Er, Tm, and Yb). -The compounds (III), (V), and (VIII) are characterized by static and dynamic magnetic measurements. (IIIc), (V), (VIIIb-d), and (VIIIf) show magnetic relaxation properties typical of single molecule magnets. As shown by single crystal XRD (V) crystallizes in the triclinic space group P1 with Z = 2 and compounds (VIIId) and (VIIIe) in the monoclinic space group P21/c with Z = 4. (V) is formed by two anionic [W5O18] 6moieties sandwiching the central Er 3+ ion. (VIIId) and (VIIIe) are composed of a central Ln 3+ encapsulated by two (β2-SiW11O39) 8units in a distorted square-antiprismatic coordination. Compounds (IIIa-c) and (V), and (VIIIa-f) are isostructural, respectively. -(ALDAMEN, M. A.; CARDONA-SERRA, S.; CLEMENTE-JUAN, J. M.; CORONADO*, E.; GAITA-ARINO, A.; MARTI-GASTALDO, C.; LUIS, F.; MONTERO, O.; Inorg.

Placing a crown on DyIII – a dual property LnIII crown ether complex displaying optical properties and SMM behaviour

“…That is, the sharp peak in w 00 below 5 K (Fig. 22,[41][42][43] This type of divergent behaviour has been observed for the family of Ln-POM SMMs which were magnetically characterized by Coronado et al [25][26][27] A single relaxation domain may be fit to the Cole-Cole model, which describes ac susceptibility as: The observation of two distinct, well-resolved pathways for magnetic relaxation at a single temperature was first described by Long et al in 2010, 40 but remains somewhat of a rarity among mononuclear SMMs.…”

“…26,47 In the selected spectral range, the emission spectra of 1 and 2 are well reproduced by two Stark components (labelled as A 1 and A 2 in Fig. 26,47 In the selected spectral range, the emission spectra of 1 and 2 are well reproduced by two Stark components (labelled as A 1 and A 2 in Fig.…”

“…12 For these complexes it has been elucidated that an easy axis, Ising type, magnetic anisotropy is favoured when the ligand field stabilizes the state with the largest projection of the total angular momentum, J. [25][26][27] These ligands have resulted in many structurally interesting complexes with remarkable magnetic properties that include a permanent magnet with a large coercive field, demonstrating that mononuclear SMMs can be as efficient as their polynuclear counterparts. 14 Amongst Ln-SMMs, such double-decker or 'sandwich'-type structures are ubiquitous, with macrocyclic ligands bound above and below the metal center.…”

Single-molecule magnet involving strong exchange coupling in terbium(iii) complex with 2,2′-bipyridin-6-yl tert-butyl nitroxide

“…4,24,25 It has already been clarified that SAPR-configured Tb-2pyNO was a SMM. 16 In the present work, the coordination structure of Tb-6bpyNO belongs to CSAPR, which is similar to SAPR.…”

Lanthanides in the frame of Molecular Magnetism

“…Attempts were done to increase the blocking temperature and rather serendipitously exciting new materials were obtained both containing one dimensional chains, Single Chain Magnets, SCM [10][11][12], and more surprising molecules containing one metal ion, Single Ion Magnets, SIM [13][14][15]. This was a kind of materials much better suited for molecules and there was soon an explosion of new systems reported and novel properties [16,17].…”