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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]

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]

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 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 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]

Abstract: A green chemistry strategy was developed to prepare two barium copper silicate pigments. Chinese purple BaCuSi2O6 and dark blue BaCu2Si2O7 are synthesized through mild hydrothermal treatment in narrow pH range. The compounds are characterized by powder X-ray diffraction techniques, infrared spectroscopy, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, luminance and magnetic measurements. When excited by a visible laser, hydrothermally synthetic BaCuSi2O6 exhibits a broad emission in the near-infrared region with an excited state lifetime 6.4 μs due to the square-planar Cu2+ ions as the chromophores. Magnetic analysis of BaCuSi2O6 indicates the spin gapped antiferromagnetic property due the presence of the Cu–Cu dimers in the structure. BaCu2Si2O7 shows interesting quasi-one-dimensional antiferromagnetic property. [Copyright &y& Elsevier]

The transformation of MnII glycolates (glc) between the three-dimensional coordination polymer [Mn(glc)2] n ( 1) and discrete mononuclear phase [Mn(glc)2(H2O)2] ( 2) can be reversibly switched by water molecules, which dramatically change the magnetocaloric effect (MCE) of MnII glycolates from the maximum of 6.9 J kg−1 K−1 in 1 to 60.3 J kg−1 K−1 in 2. This case example reveals that the effect of magnetic coupling on MCE plays a dominant role over that of other factors such as magnetic density for 3d-type magnetic refrigerants. [ABSTRACT FROM AUTHOR]

The comprehensive study reported herein provides compelling evidence that anion templates are the main driving force in the formation of two novel nanoscale lanthanide hydroxide clusters, {Gd38(ClO4)6} ( 1) and {Gd48Cl2(NO3)} ( 2), characterized by single-crystal X-ray crystallography, infrared spectroscopy, and magnetic measurements. {Gd38(ClO4)6}, encapsulating six ClO4− ions, features a cage core composed of twelve vertex-sharing {Gd4} tetrahedrons and one Gd⋅⋅⋅Gd pillar. When Cl− and NO3− were incorporated in the reaction instead of ClO4−, {Gd48Cl2(NO3)} is obtained with a barrel shape constituted by twelve vertex-sharing {Gd4} tetrahedrons and six {Gd5} pyramids. What is more, the cage-like {Gd38} can be dynamically converted into the barrel-shaped {Gd48} upon Cl− and NO3− stimulus. To our knowledge, it is the first time that the linear M-O-M′ fashion and the unique μ8-ClO4− mode have been crystallized in pure lanthanide complex, and complex 2 represents the largest gadolinium cluster. Both of the complexes display large magnetocaloric effect in units of J kg−1 K−1 and mJ cm−3 K−1 on account of the weak antiferromagnetic exchange, the high NGd/ MW ratio (magnetic density), and the relatively compact crystal lattice (mass density). [ABSTRACT FROM AUTHOR]

Two kinds of inorganic gadolinium(III)-hydroxy 'ladders', [2× n] and [3× n], were successfully trapped in succinate (suc) coordination polymers, [Gd2(OH)2(suc)2(H2O)] n ⋅ 2 n H2O ( 1) and [Gd6(OH)8(suc)5(H2O)2] n ⋅4 n H2O ( 2), respectively. Such coordination polymers could be regarded as alternating inorganic-organic hybrid materials with relatively high density. Magnetic and heat capacity studies reveal a large cryogenic magnetocaloric effect (MCE) in both compounds, namely (Δ H=70 kG) 42.8 J kg−1 K−1 for complex 1 and 48.0 J kg−1 K−1 for complex 2. The effect of the high density is evident, which gives very large volumetric MCEs up to 120 and 144 mJ cm−3 K−1 for complexes 1 and 2, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Under solvothermal conditions, one polynuclear FeIII complex of formula [Fe3{(py)C(ph)O}4Cl4][FeCl4] (1) was synthesized from reaction of phenyl-pyridine-2-yl-methanone oxime (py)C(ph)NOH with FeCl3, and one FeII/FeIII/FeII complex of composition [Fe3{(py)C(ph)NO}6][CH3COO] (2) was prepared from treatment of (py)C(ph)NOH with Fe(OAc)2. The most interesting synthetic feature of complex 1 is the in situ transformation of (py)C(ph)NOH into the (py)C(ph)O− ligand. Complexes 1 and 2 were characterized by X-ray single crystal diffraction, IR spectroscopy, and elemental analysis. X-ray analysis revealed that complex 1 contains a V-shaped FeIII core with two terminal FeIII atoms displaying distorted square-pyramidal geometries and one central FeIII ion exhibiting octahedron geometry. Complex 2 is a mixed-valence linear FeII/FeIII/FeII complex with all the three metal centers displaying distorted octahedron geometries. The low-temperature magnetic susceptibility measurement for the solid sample of 1 revealed the weak antiferromagnetic FeIII…FeIII interactions. Theoretical calculations based on density functional theory were performed using the crystal structure of complex 1. [Copyright &y& Elsevier]

Abstract: RMn2O5 (R=La, Pr, Nd, Tb, Bi) crystallites were prepared by a mild hydrothermal method and characterized by powder X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy (XPS) and magnetic measurement. The formation of manganates was sensitive to the alkalinities and Mn-containing precursors of the reaction mixtures. This family of manganates is isostructural and has a space group of Pbam. The magnetic measurements for RMn2O5 showed an antiferromagnetic transition. The strong irreversibility between the ZFC and FC curves indicated a helicoidally magnetic structure below 40K. The max d.c. susceptibilities of LaMn2O5+ δ (δ=0.01, 0.06, 0.08, 0.16, 0.17) were found to be variable and the excess oxygen (δ) in the compounds was influenced by the alkalinity used in the hydrothermal synthesis. [Copyright &y& Elsevier]

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]

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]

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]

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]

Review: [20 refs. [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]

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 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]

Abstract: The valence state and magnetic properties of hole-doped LiCuVO4 are investigated. By analyzing the Cu 2p core-level photoemission spectra, the holes are suggested to be introduced into Cu2+ site in the formation of Cu3+ ion. The calculation of effective moment also confirms the presence of nonmagnetic Cu3+ ion which should be responsible for the decrease of high-temperature susceptibility after hole doping. At low temperature, the antiferromagnetic transition at 26K and 2.3K disappears due to the enhancement of Curie term. Magnetic hysteresis at 2K shows that there exists a small ferromagnetic moment of 0.15emu/g in Li0.9CuVO4. [Copyright &y& Elsevier]

Homogeneous amorphous MnxGe1-x:H films were synthesized under thermal nonequilibrium condition by magnetron co-sputtering technology with hydrogen in Ar atmosphere. Compared to the MnxGe1-x films without hydrogen, the MnxGe1-x:H films with hydrogen show higher concentration of hole carriers, larger conductivity, and higher saturation magnetization. Moreover, it was found that the anomalous Hall resistivity is proportional to the perpendicular magnetization. These electrical and magnetic properties indicate that the ferromagnetism of the MnxGe1-x:H films is intrinsic ferromagnetism mediated by the spin-polarized hole carriers. [ABSTRACT FROM AUTHOR]

Abstract: A dinuclear oxovanadium compound [V2O2(l-his)2(2,2′-bipy)2]·[C2H6O2 ·(2,2′-bipy)] was synthesized under hydrothermal condition and characterized by single-crystal X-ray diffraction. X-ray crystallography revealed that each vanadium center is six coordinated and adopts a distorted octahedral structure. IR spectroscopy, ESR spectrum and magnetic susceptibility data for this compound are given. X-band ESR spectroscopy of the sample indicated the existence of vanadium(IV) ions in the compound. The temperature dependent magnetic susceptibility data showed the presence of a ferromagnetic coupling between the two V(IV) ions in the range 4–180K. [Copyright &y& Elsevier]

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]

Abstract: Anisotropic (Sm,Pr)Co5/Co nanocomposite particles have been fabricated by chemical coating the 2h ball milled (Sm,Pr)Co5 flakes with Co nanoparticles. The Co nanoparticles were synthesized with mean particle sizes in the range of 20–50nm. The nanocomposite particles present [001] out-of-plane texture and improved magnetic properties, e.g., an enhanced remanent magnetization of 72emu/g for (Sm,Pr)Co5/Co and 66emu/g for (Sm,Pr)Co5. In addition, by using the 8h ball milled powders (much smaller than the 2h ball milled powders) as the starting materials, Co nanoparticles can also be successfully coated on the surface of the flakes. A plausible mechanism for the formation of Co nanoparticles on the surface of (Sm,Pr)Co5 flakes is discussed. [Copyright &y& Elsevier]

Abstract: The tetranuclear cubane-like complex of the formula [Ni4(HL1)3(HL2)(H2O)(CH3OH)] [CH3COO]·2CH3OH·CH3CN (1) (H3L1=3-(2-hydroxybenzylideneamino)propane-1,2-diol; H2L2=3-aminoprppane-1,2-diol) has been prepared by a one-pot reaction of nickel(II) acetate, salicylaldehyde and 3-aminopropane-1,2-diol, where the H3L1 ligand was generated in situ via the condensation reaction between salicylaldehyde and 3-aminopropane-1,2-diol. The X-ray diffraction analysis of the complex showed a Ni4O4 cubane arrangement and the coordination environments of four Ni(II) ions are different from each other. Magnetic studies indicated ferromagnetic behavior for the complex. The magnetic data were fitted and the parameters were given as g =2.43, J 1 =15.96, and J 2 =4.116. [Copyright &y& Elsevier]

Abstract: The hydrothermal reaction of Ln(III) nitrate, Mn(II) sulfate hydrate with 5-nitroisophthalic acid (H2NIPH) produced two novel metal organic frameworks (MOFs), [Ln2Mn(NIPH)4(H2O)4]·6H2O [Ln=Eu (1), Nd (2)], which represent the first examples of three-dimensional Ln(III)–Mn(II) heterometallic MOFs based on rod-shaped molecular building blocks (MBBs). In the structures, two LnO9 polyhedra and one MnO6 polyhedron are bridged in a corner-sharing fashion to form a trinuclear unit [Ln2MnO20], which is further connected to each other by carboxylate groups to give a [Eu2MnO20]-(O-C-O)2-[Eu2MnO20] heterometallic rod. The thermal properties and magnetic properties of 1 and 2 have been investigated in the solid state. [Copyright &y& Elsevier]

A polyoxometalate [Co(phen)3][Co(en)3][Co(en)2(H2O)2][Co(en)2]0.5[ [image omitted]O40(VIVO)2] · 6H2O (1) (en = ethylenediamine, phen = 1,10-phenanthroline) has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, electron paramagnetic resonance, X-ray photoelectron spectroscopy, elemental analyses, and thermogravimetry. The structure is an interesting 3-D supramolecular network containing bi-capped Keggin-type molybdenum-vanadium clusters with transition metal complexes generated in situ under mild hydrothermal conditions. Compound 1 contains four different counteractions being coordinated complexes of cobalt. The magnetic properties of 1 have also been studied in the temperature range of 4-300 K, and its magnetic susceptibility obeys the Curie-Weiss law, showing ferromagnetic coupling. [ABSTRACT FROM AUTHOR]

Abstract: The magnetic and electron transport properties of rhombohedral Li x V y O2 (x=0.8 and y=0.8) are studied. The dc susceptibility of Li x V y O2 can be well fitted to the modified Curie–Weiss law, which verified the paramagnetic ground state. The magnetic hysteresis and ac susceptibility also confirm this paramagnetism. The Li x V y O2 exhibits semiconducting behavior, which is explained by thermal activated process at high temperature and variable-range hopping mechanism at low temperature. Anderson localization plays an important role in both the electron transport behavior and the magnetic behavior due to the site disorder between the Li+ ion and V4+ ion. [Copyright &y& Elsevier]

Abstract  Lanthanum ion (La3+)-substituted garnet nanoparticles Y3−x La x Fe5O12 (x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0) were fabricated by a sol–gel method. Their crystalline structures and magnetic properties were investigated by using X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and Mössbauer spectrum. The XRD results show that samples of Y3−x La x Fe5O12 (0.0 ≤ x ≤ 0.8) are all single phase and the sizes of particles range from 32 to 65 nm. Those of Y2LaFe5O12 consisted of peaks from garnet and LaFeO3 structures. Compared to pure YIG, the saturation magnetization is larger when the La concentration x = 0.2. However, with increasing La concentration (x), it decreases obviously. Meanwhile, may be due to the enhancement of the surface spin effects, the saturation magnetization rises as the particle size is increased. Different from the pure YIG, the Mössbauer spectra of Y2.8La0.2Fe5O12 and Y2.2La0.8Fe5O12 are composed of four sets of six-line hyperfine patterns. The results tell us that the substitution of La3+ ions with large ionic radius (1.061 Å) will give rise to a microscopic structure distortion of the a- and d-sites to different degrees, and the Zeeman sextets from a- and d-sites begin to split into two sub-sextets, which is helpful to explain the phenomenon observed in the study of the magnetic property. [ABSTRACT FROM AUTHOR]

Abstract: The Fe alloy–ferrite composites Fe–Co/Fe3O4 are synthesized by using disproportion of Fe (II) and reduction of Co (II) by Fe0 in a concentrated and boiling KOH solution. The Fe alloy and ferrites are prepared in aqueous solution without any templet and surfactants at low temperature. Their structures and magnetic properties are investigated by X-ray diffractometer (XRD) and vibrating sample magnetometer (VSM). From the results of XRD, it is shown that the samples have b.c.c and f.c.c structure of Fe, and the spinel structures of the ferrite before calcinations; the samples have b.c.c and spinel structures after calcinations at 300°C; and the samples have only f.c.c structure and the spinel structures calcined at 500°C. [Copyright &y& Elsevier]

Abstract: Nanocrystalline Co/N thin film containing Co4N phase has been deposited on Si (111) substrate by direct current magnetron sputtering in 10% N2/N2 +Ar discharge. The composition, structure and magnetic properties were examined by X-ray photoelectron spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and superconducting quantum interference device. XRD and TEM investigations showed that the grain size of nanocrystalline Co4N was in the range 10–25nm (with the error of ±0.2nm). Magnetic analysis indicated that the synthesized Co/N thin films had good in-plane anisotropy. The value of H c with the domination orientation (111) was about 97Oe. The saturation magnetization was estimated to be 103.9±6.1emu/g, which was larger than the value of 46.5emu/g firstly reported by Oda et al. [Copyright &y& Elsevier]

Abstract: Three new molybdophosphates, [Co(dien)2]·(H3dien)6·{[CoMo12O24(OH)6(HPO4)2(PO4)6][Co(Hdien)]2[CoMo12O24(OH)6(PO4)8]}·(dien)·4H3O·5H2O (1), (H3dien)4[MMo12O24(OH)6(HPO4)4(PO4)4]·10H2O [M=Co for (2), Ni for (3); dien=diethylenetriamine], have been synthesized by employing hydrothermal method and characterized by single crystal X-ray diffraction. Compound 1 is built up of Co[P4Mo6]2 units as the structural motif covalently linked by [Co(Hdien)] complex subunits to yield an unusual 1-D chain. Compounds 2 and 3 are isomorphic and both display covalent discrete M[P4Mo6]2 cluster structures which are linked by the hydrogen bonds to form 3-D supramolecular networks. Both 1 and 2 display antiferromagnetic interaction and these three compounds all exhibit intensive photoluminescence. [Copyright &y& Elsevier]

Abstract: The title layered double salt Mn3(OH)2(SO4)2(H2O)2 ·K2SO4 (1) was obtained from a simple hydrothermal reaction of CdSO4 ·8/3H2O, MnCl2 ·4H2O, α-aminopyridine (apy) and KI. X-ray analysis reveals that the two-dimensional (2-D) sheet of 1 is built up of the dimers of edge-sharing Mn(1) octahedral, extended by the apices of Mn(2) octahedral together with μ3 and μ4 SO4 groups. With free K+ ion as guest species, the 2-D sheets are further self-assembled into a 3-D supramolecular network with 1-D channels through the Ow-H⋯O hydrogen-bonded interactions. The magnetic property of 1 was investigated, and a classical behavior is observed with an antiferromagnetic order below 12.5K. [Copyright &y& Elsevier]

Abstract: Two new copper coordination polymers generated from mixed organic ligands 4,4′-bipydine and 1,2,4-benzenetricarboxylate [Cu3(1,2,4-BTC)2(4,4′-bipy)(H2O)4] 1 and [Cu(1,2,4-HBTC)(4,4′-bipy)] 2 (1,2,4-BTC=1,2,4-benzenetricarboxylate) have been prepared hydrothermally and characterized by single crystal X-ray diffraction. Compound 1 crystallizes in the noncentrosymmetric space group , with , , , , and . Its structure contains two different one-dimensional (1-D) chains for the Cu ions, namely and ; the carboxylate of 1,2,4-BTC ligands links the two different 1-D chains into an interesting steplike neutral framework. Compound 2 crystallizes in the monoclinic space group , with , , , , , . Its structure contains novel paddle-wheel clusters Cu2(CO2)4(4,4′-bipy)2 as SBUs which are further linked by monoprotonated 1,2,4-BTC ligands into a 2-D neutral framework. The magnetic behaviors of both compounds have been studied. [Copyright &y& Elsevier]