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Here we reported the deuteration of the metal‐binding equatorial water molecules in a reported HoIII single‐molecule magnet (SMM) with pentagonal‐bipyramidal geometry, from [Ho(CyPh2PO)2(H2O)5]3+ to [Ho(CyPh2PO)2(D2O)5]3+. The hyperfine structures originating from the nuclear spin of 165HoIII can be clearly observed. Moreover, the resulting magnetization dynamics revealed the switch of the relative relaxation rates for the two isotope‐isomorphic complexes—respectively faster/slower at low/high temperature. The noticeable isotope effect arises from not only the paramagnetic metal center but also the diamagnetic ligands, which can be explained by the ab initio calculated tunnel splitting and the involvement of the super‐hyperfine interaction related to the difference in the nuclear spin number of protium (1H, I=1/2) and deuterium (2H, I=1). [ABSTRACT FROM AUTHOR]

Single-molecule magnets (SMMs) are regarded as promising candidates for ultrahigh-density storage, quantum information processing and molecular spintronics. It is a crucial challenge for chemists to modulate magnetic dynamics of SMMs. Here, we successfully synthesized two 3d-4f polynuclear compounds [Co2Dy(TTTTCl)2(MeOH)]NO3·3MeOH (1) and [Co2Dy(TTTTCl)2 (MeOH)][Co(HTTTTCl)](NO3)2·2.5MeOH·2H2O (2), where H3TTTTCl=2,2′,2′′-(((nitrilotris(ethane-2,1-diyl)) tris(azanediyl)) tris(methylene))tris-(4-chlorophenol). On applying the approach by co-crystallization of bulky diamagnetic moiety, the effective energy barrier enhances from 401 K (1) to 536 K (2), which are both among the highest d-f heterometallic SMMs. [ABSTRACT FROM AUTHOR]

Abstraction of a chloride ligand from the dysprosium metallocene [(Cpttt)2DyCl] ( 1Dy Cpttt=1,2,4-tri( tert-butyl)cyclopentadienide) by the triethylsilylium cation produces the first base-free rare-earth metallocenium cation [(Cpttt)2Dy]+ ( 2Dy) as a salt of the non-coordinating [B(C6F5)4]− anion. Magnetic measurements reveal that [ 2Dy][B(C6F5)4] is an SMM with a record anisotropy barrier up to 1277 cm−1 (1837 K) in zero field and a record magnetic blocking temperature of 60 K, including hysteresis with coercivity. The exceptional magnetic axiality of 2Dy is further highlighted by computational studies, which reveal this system to be the first lanthanide SMM in which all low-lying Kramers doublets correspond to a well-defined MJ value, with no significant mixing even in the higher doublets. [ABSTRACT FROM AUTHOR]

The pentagonal bipyramidal single-ion magnets (SIMs) are among the most attractive prototypes of high-performance single-molecule magnets (SMMs). Here, a fluorescence-active phosphine oxide ligand CyPh2PO (=cyclohexyl(diphenyl)phosphine oxide) was introduced into [Dy(CyPh2PO)2(H2O)5]Br3⋅2 (CyPh2PO)⋅EtOH⋅3 H2O, and combined dynamic magnetic measurement, optical characterization, ab initio calculation, and magneto-optical correlation of this high-performance pseudo- D5 h DyIII SIM with large Ueff (508(2) K) and high magnetic hysteresis temperature (19 K) were performed. This work provides a deeper insight into the rational design of promising molecular magnets. [ABSTRACT FROM AUTHOR]

An extremely rare non-Kramers holmium(III) single-ion magnet (SIM) is reported to be stabilized in the pentagonal-bipyramidal geometry by a phosphine oxide with a high energy barrier of 237(4) cm−1. The suppression of the quantum tunneling of magnetization (QTM) at zero field and the hyperfine structures originating from field-induced QTMs can be observed even from the field-dependent alternating-current magnetic susceptibility in addition to single-crystal hysteresis loops. These dramatic dynamics were attributed to the combination of the favorable crystal-field environment and the hyperfine interactions arising from 165Ho ( I=7/2) with a natural abundance of 100 %. [ABSTRACT FROM AUTHOR]

A series of heterometallic [LnIII xCuII y] complexes, [Gd2Cu2] n ( 1), [Gd4Cu8] ( 2), [Ln9Cu8] (Ln=Gd, 3⋅Gd; Ln=Dy, 3⋅Dy), were successfully synthesized by a one-pot route at room temperature with three kinds of in situ carbonyl-related reactions: Cannizzaro reaction, aldol reaction, and oxidation. This strategy led to dysprosium analogues that behaved as single-molecule magnets (SMMs) and gadolinium analogues that showed significant magnetocaloric effect (MCE). In this study a numerical DFT approach is proposed by using pseudopotentials to calculate the exchange coupling constants in three polynuclear [Gd xCu y] complexes; with these values exact diagonalization or quantum Monte Carlo simulations have been performed to calculate the variation of the magnetic entropy involved in the MCE. For the [Dy9Cu8] complexes, local magnetic properties of the DyIII centers have been determined by using the CASSCF+RASSI method. [ABSTRACT FROM AUTHOR]

Keywords: hyperfine interaction; isotope effect; magnetization dynamics; single-molecule magnets; super-hyperfine interaction EN hyperfine interaction isotope effect magnetization dynamics single-molecule magnets super-hyperfine interaction 27074 27074 1 12/15/21 20211220 NES 211220 B Das Zusammenwirken b von kernspingetriebener Relaxation und den Liganden in Lanthanoid-Einzelmolekülmagneten (SMMs) ist nicht vollständig geklärt. Hyperfine interaction, isotope effect, magnetization dynamics, single-molecule magnets, super-hyperfine interaction Innentitelbild: Magnetization Dynamics on Isotope-Isomorphic Holmium Single-Molecule Magnets (Angew. [Extracted from the article]

Hyperfine interaction, isotope effect, magnetization dynamics, single-molecule magnets, super-hyperfine interaction Inside Cover: Magnetization Dynamics on Isotope-Isomorphic Holmium Single-Molecule Magnets (Angew. Keywords: hyperfine interaction; isotope effect; magnetization dynamics; single-molecule magnets; super-hyperfine interaction EN hyperfine interaction isotope effect magnetization dynamics single-molecule magnets super-hyperfine interaction 26870 26870 1 12/15/21 20211220 NES 211220 B Nuclear-spin driven relaxation b collaborating with the ligands in lanthanide single molecule magnets (SMMs) remains ambiguous. [Extracted from the article]

The pentagonal bipyramidal single‐ion magnets (SIMs) are among the most attractive prototypes of high performance single‐molecule magnets (SMMs). A fluorescence‐active phosphine oxide ligand is introduced, and by combining dynamic magnetic measurements, optical characterization, and ab initio calculations, the magneto‐optical correlation of a high‐performance pseudo‐D5h DyIII SIM with large Ueff = 508(2) K and high magnetic hysteresis temperature of 19 K, [Dy(CyPh2PO)2(H2O)5]Br3⋅2 (CyPh2PO)⋅EtOH⋅3 H2O (CyPh2PO=cyclohexyl(diphenyl)phosphine oxide) was studied. This work provides a deeper insight into the rational design of promising molecular magnets. More information can be found in the Full Paper by M.‐L. Tong, J.‐L. Liu, et al. on page 5708 ff. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Briefly state the design strategies for luminescent lanthanide single-molecule magnets (SMMs). • Systematically survey the recent advances of luminescent lanthanide SMMs. • Discuss the magneto-luminescent behavior for lanthanide SMMs. Abstract Incorporation of two characters into one molecular entity is an effective way to afford bifunctional molecule-based materials. Lanthanides serve as a group of preferable objectives for the construction of luminescent single-molecule magnets (SMMs) due to their excellent performances in areas of SMM and luminescence for molecular materials, showing a great potential of applications in high-density data storage, quantum computing, light-emitting diodes, biofluorescence labelling, etc. This review concentrates on the design strategies for the construction of luminescent SMMs referring to the organic chromophores and transition metal-containing chromophores as the antennas, as well as the recent examples of luminescent SMMs. To investigate the magneto-luminescent behavior (including the magneto-luminescent coupling), a few of classical complexes are discussed in the review to emphasize the importance of studying the correlation/coupling between relaxation mechanism and luminescence for lanthanide SMMs. [ABSTRACT FROM AUTHOR]

[Display omitted] • The coordination chemistry of a hexadentate mixed ligand, H 2 bbpen, is introduced. • The lanthanide single-molecule magnets based on H 2 bbpen and derivatives are reviewed and the magneto-structural correlations are analysed. • The optical and chiral-optical properties of lanthanide complexes based on H 2 bbpen and derivatives are discussed. Lanthanide complexes are among the most active frontiers of functional coordination chemistry, especially due to their fascinating magnetic and optical properties. Among them, a hexadentate mixed ligand, H 2 bbpen, gave birth to some of the best lanthanide single-molecule magnets and photoluminescence complexes. Here we review the coordination chemistry, the single-molecule magnetism and the optical properties of H 2 bbpen-based lanthanide complexes, trying to find some magneto-structural and optical-structural correlations that can promote further developments in such a family and related systems. [ABSTRACT FROM AUTHOR]