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Herein, we report two tetranuclear lanthanide complexes, of which the Dy4-complex exhibits significant single-molecule magnetic properties with the open hysteresis loop is detected until 6.5 K and a coercive field of 453 Oe is observed at 1.8 K.

Breaking the [CoN]+ core by lengthening the CoN bonds for two-coordinate Co-based complexes is a good choice to enhance the energy barrier.

A star-like CoIII2DyIII2 complex (1) and a cross-shaped CoII/III–Dy complex (2) have been obtained, in which 1 exhibits double magnetic relaxation behavior, while 2 only shows slow magnetic relaxation signals.

A novel 2D Dy-MOF and three dinuclear Dy(iii) complexes exhibit ligand-based fluorescence and single-molecule magnetic properties, and the dinuclear species undergo consecutive single-crystal to single-crystal transformation.

A five-coordinate mononuclear Dy(III) complex with a

Solvent effects on the structures and magnetic properties of single-molecule magnets (SMMs) have been of great interest for modification of the SMMs using chemical modulation. By systematically varying the reaction solvents (MeOH, ethanol

Mononuclear complexes within a particular coordination geometry have been well recognized for high-performance single-molecule magnets (SMMs), while the incorporation of such well-defined geometric ions into multinuclear complexes remains less explored. Using the rigid 2-(di(1

We report the synthesis and characterization of a single-molecule magnet composed of triangular clusters of dysprosium ions. The structural study shows that the symmetry changes from one polar point group (mm2) at room temperature to another polar point group (m) at low temperatures. Magnetic studies and theory calculations illustrate that the vortex distribution of magnetic dipoles in the triangular dysprosium clusters forms a toroidal magnetic moment. Interestingly, the analysis of AC magnetic susceptibility reveals the coexistence of three distinct magnetic relaxation processes, corresponding to the Raman, Orbach, and QTM relaxation pathways, respectively. The sum of three modified Debye functions is successfully used to describe the multiple relaxation behavior.

Taking advantage of the pentaethylene glycol (EO5) and deprotonation of EO5, a family of new structurally hexagonal bipyramidal Dy(III) complexes, [Dy(EO5)(2,6-dichloro-4-nitro-PhO)

A unique hydrogen-bonded organic-inorganic framework (HOIF) constructed from a mononuclear cobalt(II) complex, [Co(MCA)

Complexes α-Dy(depma)3Cl3 (α-DyCl), β-Dy(depma)3Cl3 (β-DyCl), and β-Dy(depma)3Br3 (β-DyBr) are reported. α-DyCl and β-DyCl are polymorphs showing distinct magnetic dynamics and luminescence properties.

A five-coordinate mononuclear Dy(iii) complex was constructed using a super bulky Schiff-base ligand, which shows a strong block of magnetization with a Ueff of ca. 1200 cm−1 and a TB of 20 K.

Single-crystal to single-crystal transformation triggered by a lattice solvent leads to reversible on–off switching of single-molecule magnet (SMM) behaviour in pentagonal-bipyramidal Dy(iii) complexes.

Electronic effect and geometry distortion of a low-symmetry ligand-field on the anisotropy barrier of spin reversal have been compared in three Dy(iii) single-ion magnets through simultaneous binding of heterodonor chelating ligands.

Fish-bone and [2 × 2] grid-like CoII-based complexes constructed using symmetrical dihydrazone ligands exhibit field-induced single-molecule magnet properties at various dc fields.

A series of Zn–Ln double-decker tetranuclear complexes display slow magnetic relaxation, in which Yb congeners show both slow magnetic relaxation and NIR properties. The magneto-structural and magneto-optical correlations are studied.

The synthesis of air-stable, high-performance single-molecule magnets (SMMs) is of great significance for their practical applications. Indeed, Ln complexes with high coordination numbers are satisfactorily air stable. However, such geometries easily produce spherical ligand fields that minimize magnetic anisotropy. Herein, we report the preparation of three air-stable eight-coordinate mononuclear Dy(iii) complexes with triangular dodecahedral geometries, namely, [Dy(BPA-TPA)Cl](BPh

High axial symmetry is also preferable for prolate shaped ErIII to behave as a high-performance SIM. A medium ligand ring of benzene is preferable for prolate shaped ErIII ion, which can induce the modest energy splitting and the small TA-QTM.

The synthesis of fluoride-bridged 1Dy, 2Dy and hepta-nuclear 3Dy dysprosium complexes is reported here and a hydroxy-bridged dinuclear dysprosium complex 4Dy is synthesized for comparison.

Dry eye disease (DED), a complex ocular surface disease with a high prevalence rate, is associated with corneal injury, excess oxidative stress and inflammation. Current therapeutic strategies, including artificial tears and anti-inflammatory agents, are unable to address all the deleterious factors or to achieve a clinical cure due to their temporary or side effects. Here, we prepared a multiple-functional eyedrop based on the deposition of gold nanoparticles (AuNPs) reduced by ascorbic acid (AA) onto the exosomal phospholipid membrane of mesenchymal stem cell (mExo)-derived exosomes

Complete-active-space self-consistent field and N-electron valence second-order perturbation theory have both been employed to investigate the magnetic anisotropy of one two-coordinate cobalt(II) compound

Eight square-pyramidal dysprosium complexes of the type [Dy(X)(DBP)2{TMG(H)}2] were synthesized, where TMG(H) denotes 1,1,3,3-tetramethylguanidine, X denotes an alkoxide ligand or anionic guanidina...

Photosensitive lanthanide-based single-molecule magnets (Ln-SMM) are very attractive for their potential applications in information storage, switching, and sensors. However, the light-driven structural transformation in Ln-SMMs hardly changes the coordination number of the lanthanide ion. Herein we report for the first time that X-ray (λ = 0.71073 Å) irradiation can break the coordination bond of Dy-OH2 in the three-dimensional (3D) metal-organic framework Dy2(amp2H2)3(H2O)6∙4H2O (MDAF-5), where the {Dy2(OPO)2} dimers are crosslinked by dianthracene-phosphonate ligands. The structural transformation proceeds in a single-crystal-to-single-crystal (SC-SC) fashion, forming the new phase Dy2(amp2H2)3(H2O)4∙4H2O (MDAF-5X). The phase transition is accompanied by a significant change in magnetic properties due to the alteration in coordination geometry of the DyIII ion from a distorted pentagonal bipyramid in MDAF-5 to a distorted octahedron in MDAF-5-X.

Controllable synthesis of uniformly distributed nanowires of coordination polymers with inherent physical functions is highly desirable but challenging. In particular, the combination of chirality and magnetism into nanowires has potential applications in multifunctional materials and spintronic devices. Herein, we report four pairs of enantiopure coordination polymers with formulae S-, R-Dy(cyampH)3 ⋅ CH3 COOH ⋅ 2H2 O (S-1, R-1), S-, R-Dy(cyampH)3 ⋅ 3H2 O (S-2, R-2), S-, R-Dy(cyampH)2 (C2 H5 COO) ⋅ 3H2 O (S-3, R-3) and S-, R-Dy(cyampH)3 ⋅ 0.5C2 H5 COOH ⋅ 2H2 O (S-4, R-4) [cyampH2 =S-, R-(1-cyclohexylethyl)aminomethylphosphonic acids], which were obtained depending on the pH of the reaction mixtures and the specific carboxylic acid used as pH regulator. Interestingly, compounds 3 were obtained as superlong nanowires, showing 1D neutral chain structure which contains both phosphonate and propionate anion ligands. While compounds 1, 2 and 4 appeared as block-like crystals, superhelices and nanorods, respectively, and exhibited similar neutral chain structures containing only phosphonate ligand. Slow magnetization relaxation characteristic of single-molecule magnet (SMM) behavior was observed for compounds S-1 and S-3. Theoretical calculations were performed to rationalize the magneto-structural relationships.

One mononuclear complex [Dy(Htpy)(NO3)2(acac)] (1) and a tpy--extended 1D chain {[Dy(CH3OH)(NO3)2(tpy)]·CH3OH}n (2) (Htpy = 4'-(4-hydroxyphenyl)-2,2':6',2''-terpyridine, Hacac = acetylacetone) were successfully designed to investigate the effect of bond length tuning around the DyIII cation on the magnetic dynamics of single-molecule magnets (SMMs). Interestingly, two magnetic entities possess the same local coordination sphere (N3O6-donor) as well as the configuration (Muffin, Cs) of dysprosium centers. Only a slight difference in structure results from purposefully substituting the acetylacetone ligand in 1 with hydroxyl oxygen from tpy- linkage and one methanol molecule in 2. However, the remarkable differences in dynamics behavior were clearly found between them. Compound 1 possesses a thermal-activated effective energy barrier (Ueff/kB) of 22.7 K under a 0 kOe direct current (dc) field and negligible hysteresis loop at 2.0 K, while complex 2 shows high-performance SMM behavior with the largest energy barrier of 354.36 K among the reported nine-coordinated DyIII-based systems and the magnetic hysteresis up to 4.0 K at a sweep rate of 200 Oe s-1. These experimental results combined with the previous reported data reveal that the shortest bond and the bond length difference around the DyIII center synergistically determine the dynamics of SMMs. The uniaxial anisotropy increases with the decrease of the shortest bond and the increase of the bond length difference, which is confirmed by the theoretical calculations.

Two series of lanthanide complexes of two imidazole-substituted nitronyl nitroxide biradicals have been synthesized and characterized structurally and magnetically.

By incorporating photoreactive anthracene moieties into binuclear Dy

Terminal fluoride ligands generate strong magnetic anisotropy in air-stable chiral dysprosium enantiomers supported by a bulky equatorial macrocycle, exhibiting a typical zero-field single-molecule magnet behaviour.

Two lanthanide single-molecule magnets (SMMs) [Dy

A centrosymmetric dinuclear Dy-based complex, Dy2L2(H2L)Cl2(EtOH)2, was successfully synthesised, and exhibits a typical SIM behaviour and unusual triple relaxation pathways.

Density functional theory (DFT) and ab initio calculations were performed to probe the origin of the magnetic relaxation barriers for two finite single-chain magnets (SCMs) featuring a one-dimension chain, Co(hfac)2(R-NapNIT) (R-NapNIT = 2-(2'-(R-)naphthyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, R = MeO (1) or EtO (2)). Our calculations show that the strong intrachain CoII-CoII exchange coupling interactions transmitted by radicals can contribute much more than ionic anisotropy to the height of the reversal barrier of magnetization for the single-chain magnets (SCMs) with |2E| < |4J/3|. In addition, the anisotropic energy barrier ΔA decreases with the decrease of |2E/J| ratio and finally vanishes in the limit of broad domain walls (|2E| < < |4 J/3|). Therefore, the total magnetic relaxation energy barriers of two SCMs mostly originate from the correlation energy barrier Δξ deriving from the indirect ferromagnetic interaction between CoII-CoII transmitted by the strong CoII-radical antiferromagnetic interactions.