Evolution from a single relaxation process to two-step relaxation processes of Dy₂ single-molecule magnets via the modulations of the terminal solvent ligands

Abstract

To explore the influences of the magnetic interactions on the relaxation dynamics of single-molecule magnets (SMMs) and to understand the relationship between single-ion relaxation and the relaxation of a molecular...

Three angular Zn2Dy complexes showing the effect of remote coordination at Zn and counter ions on slow magnetic relaxation at Dy centres

“…Despite the presence of two crystallographically independent dysprosium sites for 1 , the fitting of the Cole–Cole plots with the generalized Debye model yields α values in the range of 0.311–0.407 (Table S3, ESI†), indicating a moderate distribution of relaxation times. 52 From these data, the relaxation time, τ , could be extracted in order to analyse the relaxation dynamics. The ln( τ ) vs. T plot (Fig.…”

Solvent Modification of the Structures and Magnetic Properties of a Series of Dysprosium(III) Single-Molecule Magnets

“…23 Furthermore, the lattice solvent molecules can also sometimes change the symmetry of the crystals and lead to a different number of the crystallographic unique Ln III centers, which can lead to the appearance of multiple relaxation processes. 24 Fourth, modification of the Ln-SMMs through solvents can sometimes occur in the solid state through a desolvation/ solvation process and, even more interestingly, in a reversible single-crystal-to-single-crystal manner. Up to now, several Ln III complexes with these solvent-switchable properties have been reported.…”

“…In addition, Liu et al also reported four very similar Cu 3 Tb 2 compounds where the noncoordinated solvents [methanol (MeOH), ethanol (EtOH), propanol (PrOH), and water (H 2 O)] can have a continuous modification of their energy barriers . Furthermore, the lattice solvent molecules can also sometimes change the symmetry of the crystals and lead to a different number of the crystallographic unique Ln III centers, which can lead to the appearance of multiple relaxation processes …”

Macrocycle supported dinuclear lanthanide complexes with different β-diketonate co-ligands displaying zero field single-molecule magnetic behaviour

“…7 Among several ligand systems employed for the development of Dy-SMMs, Schiff base ligands possessing rich N/O donor sites have been extensively used in the synthesis of such SMMs mainly due to their ease of synthesis and possible modulation of electronic and steric properties by suitable choice of carbonyl and amine components. 8 In our previous work, we successfully isolated some lanthanide complexes with a symmetrical dinucleating Schiff base ligand derived from 4-chloro-2,6-diformylphenol and N , N -dimethyldipropylenetriamine in which Dy analogues displayed SMM properties. 9 Remarkably, the metal assisted in situ macrocyclization of the acyclic heptadentate N 6 O donor Schiff base ligand was observed in the presence of co-ligands (acetylacetone or its derivative) by defragmentation of some parts of the ligands.…”