A family of mono-, di-, and tetranuclear Dy^IIIcomplexes bearing the ligand 2,6-diacetylpyridine bis(picolinoylhydrazone) and exhibiting slow relaxation of magnetization

Abstract

The systematic investigation of the general reaction scheme DyIII/X-/LH2, where X- = Cl-, CF3SO3-, ClO4-, MeCO2-, and LH2 is the pocket-type ligand 2,6-diacetylpyridine bis(picolinoylhydrazone), resulting from the condensation of 2,6-diacetylpyridine...

Structures and Single-Molecule Magnet Behavior of Dy3 and Dy4 Clusters Constructed by Different Dysprosium(III) Salts

“…For the 1 _ Dy2 ion, the all-oxygen coordination environment might not be conducive to the matching of the crystal field . The transverse component of the ground state was large enough to increase the tunneling rate of 1 at low temperatures, thus inhibiting the occurrence of magnetic relaxation behavior , (Tables S8–S9). The Dy–O bond length in 2 was significantly smaller than the bond lengths of the other atoms to the Dy III ion, which generally made the complex more axial.…”

“…To explore the magneto-structural correlations of tetranuclear Dy III -based SMMs, this class of complexes were summarized (Table S13). − The nuclear centers of tetranuclear Dy III complexes have various shapes such as linear, cymbiform, and parallelogram. (Figure ).…”

Peripheral site modification in a family of dinuclear [Dy2(hynad)2–6(NO3)0–6(sol)0–2]0/2− single-molecule magnets bearing a {Dy2(μ-OR)2}4+ diamond-shaped core and exhibiting dissimilar magnetic dynamics

“…1b and 3b). 43 To this end, in 1 , the equatorial pentagonal plane, which encompasses the oblate Dy III center, is made of O1, O2, O4, O5, and O8 atoms, while the basal trigonal plane and the single atom vertex of the muffin, which are located below and above the DyO 5 plane, are formed by O6, O8′, O10′, and O9 atoms, respectively. 44 Interestingly, the stronger Dy–O bonds within the muffin topology are distributed among the atoms occupying both the equatorial pentagon [Dy1–O1 = 2.286(2) and Dy1–O8 = 2.331(2)] and the axial triangular [Dy1–O8′ = 2.332(3)] subunits, likely causing a disorientation of the magnetic anisotropy from the pure axiality which explains the small U eff value of 1 .…”

Dysprosium Clusters from 3-Ethoxysalicylidene Terminal-Decorated Acylhydrazone Ligands: In Situ Ligand Transformation-Assisted Assembly and Zero-Field Single-Molecule Magnet Behaviors

“…Upon cooling, the χ M T values of 1 and 2 all decline gradually, finally reaching the minimum of 67.65 and 33.86 cm 3 K mol –1 at 2 K, respectively. These decreases could be ascribed to the combined effects of the quenching of Stark energy levels of Dy III ions and possible antiferromagnetic interactions between the Dy III centers in the systems. − The χ M T–T curve of 3 exhibits a gradually decreasing trend in a high-temperature region due to the thermal depopulation of the Stark levels of Dy ions. Note that a shoulder appears at about 20–10 K, after which the χ M T value starts to drop rapidly, finally reaching a minimum of 48.4 cm 3 K mol –1 at 2 K. This might be ascribed to the presence of weak ferromagnetic interactions between the Dy centers of 3 . ,− …”