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We explored the coupling between magnetic and magneto-transport properties in MnBi2Te4 crystals with Fermi energy EF ranging from 10 to 100 meV in the conduction band. Electrical, magnetic, and magneto-transport measurements reveal distinct behaviors depending on EF. At lower EF values (10 meV), MnBi2Te4 exhibits degenerate-semiconductor-like electrical transport and ferrimagnetism, with weak coupling between magneto-resistance and ferrimagnetism. In contrast, MnBi2Te4 displays metallic transport and antiferromagnetism (AFM) at higher Fermi energies, with magneto-resistance strongly coupled to antiferromagnetism and canted antiferromagnetism under a large external magnetic field. Remarkably, Hall measurements demonstrate a pronounced anomalous Hall resistivity (AHR) when the EF of MnBi2Te4 is 10 meV, larger than that reported for other bulk MnBi2Te4 crystals in the literature. Significant AHR is attributed to the Berry-phase effect in electronic-band structure based on first-principles calculation. The evolution of magnetic and magneto-transport properties in EF shifted MnBi2Te4 can be semi-quantitatively explained by the Ruderman–Kittel–Kasuya–Yosida interaction between neighboring MnTe layers. Our work suggests that the strongly Fermi-energy-sensitive magneto-transport properties observed in MnBi2Te4 may be useful in developing magnetic sensors/detectors. [ABSTRACT FROM AUTHOR]

A novel Bi 12 O 15 Cl 6 /NiFe 2 O 4 (CN) photocatalyst with both recyclability and efficient photocatalytic performance was synthesized by the hydrothermal method and achieved practice value enhancement. The optimal composite was identified as Bi 12 O 15 Cl 6 combined with 5 wt% NiFe 2 O 4 (CN-5), exhibiting the capability to decompose 98.2% of RhB within 90 min. Remarkably, the photocatalytic activity remained above 90% even after 4 recycling cycles, and the magnetization saturation reached 2.6 emu/g, showcasing exceptional magnetic properties and photocatalytic stability. Meanwhile, characterization analysis proved successful compounding of NiFe 2 O 4 , and the specific surface area of CN-5 was slightly enhanced. The heterojunction structure generated by direct binding in CN-5 significantly reduced the photogenerated carrier complexation rate. Moreover, the photocatalytic mechanism indicated that the degradation of RhB followed the Z-type heterojunction mechanism, and photo-induced ·O 2 − played a pivotal role, followed by h+ and ·OH. In summary, the composite magnetic photocatalyst Bi 12 O 15 Cl 6 /NiFe 2 O 4 could offer a promising alternative for wastewater purification. • Novel magnetic composite Bi 12 O 15 Cl 6 /NiFe 2 O 4 displayed remarkable photocatalytic properties. • Bi 12 O 15 Cl 6 /NiFe 2 O 4 offers economic viability and environmental sustainability. • A Z-type heterojunction was generated directly between Bi 12 O 15 Cl 6 and NiFe 2 O 4. [ABSTRACT FROM AUTHOR]

Here, we report the growth of (Sr, Ca) Nd2Fe2O7 single crystals with the Ruddlesden–Popper structure using an optical floating-zone method. A significantly anisotropic magneto-dielectric effect (MD), ab-plane and c-axial MD coefficients reaching −12.3% and −8.4% measured at 103 Hz in a 1 T magnetic field, can be obtained in a SrNd2Fe2O7 crystal at room temperature. The corresponding anisotropic MD ratio can be reached as high as 1.46. With an increase in the Ca concentration, the MD effect decreases dramatically and is eventually completely suppressed in both directions. Analysis of magnetic properties and 57Fe Mössbauer spectra suggests that the anisotropic MD effects in SrNd2Fe2O7 can be attributed to polaronic hopping between two neighboring Fe3+ ions through oxygen vacancies in an anisotropically antiferromagnetic matrix; the disappearance of the MD effect in Ca-doped SrNd2Fe2O7 is a consequence of the suppression of the antiferromagnetism. Our work suggests that the significantly anisotropic MD effect in SrNd2Fe2O7 crystals at room temperature can be used in magneto-dielectric controlled devices. [ABSTRACT FROM AUTHOR]

In this paper, LaFe0.75Cr0.25O3 was synthesized by a citric acid combusting sol–gel method. The basic structural information is reflected by XRD. According to Mössbauer spectroscopy, the inhomogeneous distribution of Cr contributes to magnetic dilution, thus appearing the coexistence of singlet and sextet. Simultaneously, the rare superparamagnetic relaxation appears due to "critical superparamagnetism" caused by small magnetic clusters with intervening sizes. Oxygen vacancies of synthesized sample are also found. The DC magnetization curve reveals the magnetization reversal phenomenon, which is related to the competition between the Dzyaloshinsky–Moriya interaction (DMI) and the magnetic anisotropy belonging to single ions. At 300 K, LCFO reveals weak magnetism. No magnetic transition is observed below 400 K. [ABSTRACT FROM AUTHOR]

Abstraction of iodide from [(η5‐C5iPr5)2UI] (1) produced the cationic uranium(III) metallocene [(η5‐C5iPr5)2U]+ (2) as a salt of [B(C6F5)4]−. The structure of 2 consists of unsymmetrically bonded cyclopentadienyl ligands and a bending angle of 167.82° at uranium. Analysis of the bonding in 2 showed that the uranium 5f orbitals are strongly split and mixed with the ligand orbitals, thus leading to non‐negligible covalent contributions to the bonding. Investigation of the dynamic magnetic properties of 2 revealed that the 5f covalency leads to partially quenched anisotropy and fast magnetic relaxation in zero applied magnetic field. Application of a magnetic field leads to dominant relaxation by a Raman process. [ABSTRACT FROM AUTHOR]

A wheel-shaped Dy(iii) single-molecule magnet (SMM), supported by polyoxotungstates, Cs15K8Na12[K⊂{(AsW9O33)Dy(H2O)2}6]·71H2O (1), is described here. The polyanion of 1 possesses an idealized S6 symmetry. The effective energy barrier (68 K) obtained from magnetic studies is consistent with the deconvolution of the luminescence spectra of 1. [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]

Two dysprosium aggregates, formulated as [Dy2(μ-OH)2(H2bpte)2Cl2(MeOH)2]Cl2 (1), and [Dy8(μ-OH)8(bpte)8]·24H2O (2) (H2bpte = 1,2-bis(3-(pyridin-2-yl)-1H-1,2,4-triazol-5-yl)ethane), were obtained using solvothermal reactions. Upon changing the metal salt and synthetic reaction conditions, an eight-member {Dy8} (2) ring was isolated. Complex 1 is centrosymmetric in which two {Dy2} clusters are connecting to each other through the hydrogen bonding. Complex 2 forms an eight-member DyIII ring with an inner diameter of 4.5 Å and is the first reported {Dy8(μ-OH)8} core in lanthanide-hydroxo clusters. The H2bpte ligand displays trans,trans- and cis,cis-coordination modes in 1 and 2, respectively. Alternating current (ac) magnetic measurements of both complexes were carried out. In 1, the out-of-phase susceptibilities (χ′′M) below 9 K confirm the slow relaxation of magnetization, which is a typical characteristic of single-molecule magnets (SMMs). [ABSTRACT FROM AUTHOR]

Two coordination polymers [Cu(Hpptz)]·H 2 O ( 1 ) and [Co(Hpptz)(OH)]·H 2 O ( 2 ) [Hpptz = 5-(4-((1H-pyrazol-1-yl)methyl)-phenyl)-5H-tetrazole] were hydrothermally synthesized and characterized by elemental analysis, IR, PXRD and TGA. 1 and 2 are featured similar 22-membered M 2 L 2 rings with close metal pitch and stacking interactions, however, two different 3D supramolecular topological architectures are obtained due to the different coordination modes of the metals. The magnetic and catalytic properties of 2 are also investigated. The results indicate that 2 demonstrates frequency-dependent magnetic behavior and moderate catalytic activity toward Claisen Schmidt reaction of nitrobenzaldehyde and acetone. [ABSTRACT FROM AUTHOR]

The area of molecular magnetic coolants has developed rapidly in recent years. A large number of competitive candidates have been reported, with the cooling performances chasing each other. In this account, four explicit strategies, namely, increasing ground-state spin, reducing magnetic anisotropy, weakening magnetic interactions, and lowering the molecular weight, are proposed from the theoretical viewpoint towards improving the magnetocaloric effect (MCE). According to this guidance, these successful strategies are discussed to pursue excellent magnetic coolants. This is accompanied by a discussion of the representative examples reported by our group. The magnetic entropy change increases from one compound to another, which in the most pronounced cases is suggestive of being the largest MCE in magnetic coolants. [ABSTRACT FROM AUTHOR]

A series of heterometallic 3d-Gd3+ complexes based on a lanthanide metalloligand, [M(H2O)6][Gd(oda)3] ⋅3 H2O [M=Cr3+ ( 1-Cr)] (H2oda=2,2′-oxydiacetic acid), [M(H2O)6][MGd(oda)3]2 ⋅3 H2O [M=Mn2+ ( 2-Mn), Fe2+ ( 2-Fe) and Co2+ ( 2-Co)], and [M3Gd2(oda)6(H2O)6] ⋅12 H2O [M=Ni2+ ( 3-Ni), Cu2+ ( 3-Cu), and Zn2+ ( 3-Zn)], are reported. Magnetic and heat-capacity studies revealed a significant impact on the magnetocaloric effect depending on the anisotropy of the 3d transition metal ions, as confirmed by comparison of the observed maximum values of −Δ Sm between complexes 2-Co and 1-Cr. In these two complexes, the 3d metal ions have the same spin ( S=3/2 for Co2+ and Cr3+ ions), and the theoretical calculation suggested a larger −Δ Sm value for 2-Co (47.8 J K−1 kg−1) than 1-Cr (37.5 J K−1 kg−1); however, the significant anisotropy of Co2+ ions in 2-Co, which can result in smaller effective spins, gives a smaller value of −Δ Sm for 2-Co (32.2 J K−1 kg−1) than for 1-Cr (35.4 J K−1 kg−1) at Δ H=9 T. [ABSTRACT FROM AUTHOR]

Based on the analogous kagomé [Co3(imda)2] layers (imda=imidazole-4,5-dicarboxylate), a family of pillar-layered frameworks with the formula of [Co3(imda)2(L)3] ⋅(L) n ⋅ xH2O ( 1: L=pyrazine, n=0, x=8; 2: L=4,4′-bipyridine, n=1, x=8; 3: L=1,4-di(pyridin-4-yl)benzene, n=1, x=13; 4: L=4,4′-di(pyridin-4-yl)-1,1′-biphenyl, n=1, x=14) have been successfully synthesized by a hydrothermal/solvothermal method. Single-crystal structural analysis shows a significant increase in the interlayer distances synchronized with the extension of the pillar ligands, namely, 7.092(3) ( 1), 10.921(6) ( 2), 14.780(5) ( 3), and 19.165(4) Å ( 4). Despite the wrinkled kagomé layers in complexes 2- 4, comprehensive magnetic characterizations revealed weakening of interlayer magnetic interactions and an increase in the degree of frustration as the pillar ligand becomes longer from 1 to 4; this leads to characteristic magnetic ground states. For compound 4, which has the longest interlayer distance, the interlayer interaction is so weak that the magnetic properties observed within the range of temperature measured would correspond to the frustrated layer. [ABSTRACT FROM AUTHOR]

A Hoffman-like coordination polymer with appreciable porosity and uncoordinated pyridyl groups, namely, [Fe(2,5-bpp){Au(CN)2}2] ⋅ x Solv (2,5-bpp=2,5-bis(pyrid-4-yl)pyridine; Solv=solvent), was synthesised and characterised. A series of fascinating spin-crossover behaviours with abrupt, stepwise and hysteretic features were obtained by exchange with a range of protic solvents (ethanol, n-propanol, isopropyl alcohol, sec-butanol and isobutanol). Guest-host hydrogen-bonding interactions involving the H-accepting site of the framework are primarily responsible for the pronounced cooperativity of these spin-crossover behaviours. Meanwhile, the tunable critical temperatures over a range of about 130 K are presumably attributable to a certain degree of competition between internal pressure and local electronic influences of solvents. [ABSTRACT FROM AUTHOR]

A record anisotropy barrier (319 cm−1) for all d-f complexes was observed for a unique FeII-DyIII-FeII single-molecule magnet (SMM), which possesses two asymmetric and distorted FeII ions and one quasi- D5 h DyIII ion. The frozen magnetization of the DyIII ion leads to the decreased FeII relaxation rates evident in the Mössbauer spectrum. Ab initio calculations suggest that tunneling is interrupted effectively thanks to the exchange doublets. [ABSTRACT FROM AUTHOR]

Iron-based soft magnetic composites with phosphate-polyimide (PI) insulating layer were successfully fabricated by phosphating and imidization. The effect of phosphoric acid content on microstructure and compressibility of iron powder, and magnetic properties of the cores were investigated. The results demonstrate that the inner inorganic coated layer mainly consists of iron phosphate and ferrous phosphate. With increasing phosphoric acid content, the thickness of phosphate increases gradually, resulting in the reduction of density, maximum permeability and magnetic induction intensity. When the content of phosphoric acid reaches above 0.3 wt%, the bonding strength between the PI coating and iron particles is reduced, leading to the breakage of insulating layer and the augment of core loss. Owing to the excellent thermal stability of PI, magnetic powder cores can be cured at the temperature up to 400 °C. The sample coated with 0.1 wt% phosphoric acid and 1.5 wt% PI exhibits excellent magnetic properties. The maximum permeability reaches 201.4, and the core loss (186.6 mW/g) is less than 15% of monolayer phosphate coated sample (measured at 50 mT and 100 kHz). Additionally, the corrosion resistance of the sample is significantly improved. • Iron-based soft magnetic composites were fabricated by phosphating and imidization. • The phosphate-polyimide coated SMCs can be cured at the temperature up to 400 °C. • The effect of phosphoric acid content on the magnetic properties was investigated. • Magnetic core exhibits lower core loss and higher maximum permeability. [ABSTRACT FROM AUTHOR]

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]

Review: [20 refs. [ABSTRACT FROM AUTHOR]

Abstract In 2016, our group first reported a single-ion magnet (SIM) [Dy(bbpen)Br] (H 2 bbpen = N , N ′‑bis(2‑hydroxybenzyl)‑ N , N ′‑bis(2‑methylpyridyl)ethylenediamine) with the highest effective energy barrier (U eff) over 1000 K. To explore further for the high performance single-ion magnets (SIMs), we used functional ligand to replace the Br− anion. The H 2 bbpen and 4′‑(1,2,2‑triphenylvinyl)benzoic acid (tpe-COOH) ligand with aggregation-induced-emission-active (AIE) property, formed a triangular dodecahedral SIM, [Dy(bbpen)(tpe-COOH)]⋅2MeOH. The structural, magnetic and luminescent properties of the SIM have been investigated. Related to its lower local symmetry around Dy(III) ion, the U eff was sharply reduced to 77 K under an external dc field of 0.15 T. Therefore, it proved the importance of local symmetry to get the high performance SIMs from the opposite side. Graphical abstract A Dy(III) triangular dodecahedral complex based on H 2 bbpen and tpe-COOH ligands has been synthesized, which exhibited field-induced single-ion magnet behavior. Unlabelled Image Highlights • A Dy(III) triangular dodecahedral complex based on H 2 bbpen and tpe-COOH ligands has been synthesized. • It exhibited field-induced single-ion magnet behavior. • It proved the importance of local symmetry to get the high performance single-ion magnet from the opposite side. [ABSTRACT FROM AUTHOR]

• The thermomagnetic curve of NdFe 0.5 Cr 0.5 O 3 composite system was simulated by molecular field model and Monte Carlo method. • It was found that due to the random distribution of B site ions in NdFe 0.5 Cr 0.5 O 3 , cluster complexes with multiple Fe or Cr are easy to appear, and have complementary proportions. • In the process of spin reorientation, the effective spin of Nd3+ion at A site will also change with temperature. • The exchange constant of each phase in the composite system is estimated. Sophisticated spin instruments require high-precision spin control. In this study, we accurately study the intrinsic magnetic properties of the strongly disordered system NdFe 0.5 Cr 0.5 O 3 through molecular field models combined with anti-site defects (ASD) theory. The three constituent sub-magnetic phases of the system are separated, and their magnetization contributions are calculated separately. Fitting the angle of the A/B magnetic moment at a given temperature, the reorientation temperature point and temperature dependence of different magnetic phases are obtained. This research will provide a very good theoretical support for studying complex disordered systems and applying high-precision spin control and lay a foundation for the design of new functional materials. [ABSTRACT FROM AUTHOR]

Application of pristine and (2.5–5) wt% Ni, Cu doped SnO 2 as adsorbent for the removal of Malachite green (MG) dye under natural solar light has been investigated in the present study. Synthesized nanostructures are characterised by XRD, XPS, BET, FESEM and UV–Visible spectroscopy. Sorption data were examined using Lagergren's pseudo first order, second order and intra particle diffusion kinetic models. Pseudo second order kinetic model was found suitable for describing the adsorption mechanism in this study. The calculated thermodynamic parameters revealed the endothermic, spontaneous and thermodynamically feasible nature of sorption mechanism of MG dye onto pristine and doped SnO 2 nanostructures. Compared with other samples, 5% Cu doped SnO 2 showed better photocatalytic degradation efficiency by removing 81.42% percentage of initial dye concentration within 240 min of contact time. SQUID measurement gave an account on the existence of ferromagnetic behaviour for Ni and Cu doped SnO 2 nanostructures. • Cost effective and capping agent free synthesis of Cu/Ni doped SnO 2 hexagonal nanorods by hydrothermal route. • Characterizations using XRD, XPS, BET, FESEM and UV–Visible spectroscopy. • Evaluation of adsorption and solarlight photocatalytic performance of Cu/Ni doped SnO 2 by taking malachite green as model dye. • Investigation on adsorption kinetics using Lagergren's pseudo first order, second order and intra particle diffusion kinetic models. • Analysis of the role of Ni/Cu doped SnO 2 as a photocatalyst as well as ferromagnetic material. [ABSTRACT FROM AUTHOR]

Two cobalt(II) homometallic complexes, [Co 2 (HTDA) 2 (H 2 O) 6 ·2H 2 O] (1) and {[Co 3 (TDA) 2 (H 2 O) 8 ]·H 2 O} n (2) (H 3 TDA = 1 H -1,2,3-triazole-4,5-dicarboxylic acid) have been synthesized and structurally characterized in detail. Single-crystal X-ray crystallographic study reveals that they crystallize in trigonal space group R -3 and orthorhombic space group Pna 2 1 , respectively. In 1 , two Co 2 + cations are bonded by two HTDA 2 − ligands to generate a binuclear Co II unit, which can further be extended to a 3D supermolecular structure via the hydrogen bonds. At variance with 1 , the nearest Co 2 + cations of 2 are connected via TDA 3 − ligands to form a 1D coordination polymer and can be further linked to each other to result in a 3D supermolecular framework through the hydrogen bonding interactions as well. The magnetic properties of them were studied in detail. [ABSTRACT FROM AUTHOR]

The magnetic and magneto-transport properties of amorphous CoO 1− v films have been systematically studied and manipulated by changing the concentration of oxygen vacancies. A giant exchange bias field H E ≈4380 Oe and a large coercivity H C ≈8500 Oe are observed at 5 K for the composite films. And, a metal to insulator transition has been demonstrated in CoO 1− v films by decreasing the concentration of oxygen vacancies. Moreover, a remarkable decrease of the exchange bias and a slight increase of the saturation magnetization can be obtained by modifying the microstructures through post-thermal annealing. [ABSTRACT FROM AUTHOR]