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Abstract Rare earth metals (REMs), such as Dysprosium (Dy) and Ytterbium (Yb), have experienced unprecedented demand in recent times due to their applications in high-end technologies. REMs are found only in select geographic locations placing tremendous economic constraints on their use. In this work, we have developed Gum Acacia-grafted hydrogels (GmAc-FluoroTerPs) that are capable of selective detection and capture of Dy and Yb. The intrinsically blue fluorescent polymer hydrogel GmAc-FluoroTerP has been optimized for Dy(III) and Yb(III) specific quenching, enabling limit of detection of the REMs at 0.13 nM and 60.8 pM, respectively. A comprehensive structural characterization of the fluorescent hydrogel has been performed via NMR, FTIR, XPS, EPR, TGA, XRD, TEM, SEM, EDX, TCSPC, and DLS. In addition to an in situ generated fluorophore, GmAc-FluoroTerP displays a distinctive aggregation induced emission enhancement in mixed solvents. The complexation of Dy(III)/Yb(III) with GmAc-FluoroTerP hydrogel has been characterized by XPS, TCSPC, and logic gate analyses, and the adsorptive capacity for Dy(III) and Yb(III) are found to be best reported till date as 125.57 mg g−1 and 102.27 mg g−1, respectively. Desorption at acidic pH allows recovery of the REMs. We also report semiconducting behaviour of the native fluorescent hydrogel, that is enhanced upon adsorptive capture of Dy(III) and Yb(III), with calculated band gaps at 1.37, 0.77, and 0.49 eV, respectively. The convergent sensing, capture, and reuse of Dy(III) and Yb(III) presented in this work promises a hitherto unreported template for application on other REMs.

Magnetocaloric properties of TbCrO3 and TmCrO3 are reported and compared with those of the previously reported rare-earth chromites RCrO3 (R = Gd, Dy, Ho, and Er) and other perovskite-type oxides. The samples of TbCrO3 and TmCrO3 in this work were synthesized using a citrate gel combustion technique, and their magnetic properties were investigated and compared with those reported previously on RCrO3 (R = Gd, Dy, Ho, and Er). The Cr3+–Cr3+ ordering temperatures were found to strongly depend on the ionic radii of the rare-earth. By fitting the dc magnetization data with modified Curie–Weiss law including the Dzyaloshinsky–Moriya antisymmetric exchange interaction (D) and the symmetric exchange constant Je, spin canting angles (α) were obtained. In general, α was found to increase with the decreasing ionic radii of R3+ in RCrO3. The magnetocaloric properties investigated included the magnetic entropy change (−ΔS) for a given change in magnetic field (ΔH), the corresponding adiabatic temperature change (ΔTad), and their relative variations (ΔTad/ΔH) and (−ΔS/ΔH). It is observed that for RCrO3, (−ΔS) measured in the vicinity of the ordering temperature of R3+–R3+, varies almost as G2/3 where G is the de Gennes factor. Among RCrO3, GdCrO3 shows the largest value of (−ΔS/ΔH), because of its largest G factor and its magnitudes of (ΔTad/ΔH) and (−ΔS/ΔH) compare well with the reported values for the perovskites GdFeO3 and EuTiO3. These comparisons presented here provide useful information on the potential use of these materials in magneto-refrigeration technology. [ABSTRACT FROM AUTHOR]

For photocatalysis technology to be applied industrially, there has been a significant increase in the need for visible-light-driven photocatalysts that possess exceptional superparamagnetic characteristics to facilitate easy separation. Hence, in this study, rare earth elements (RE) (Sm, Yb, Dy, Er, and Ho) were systematically doped into manganese ferrite (MF) using the coprecipitation method to serve two purposes, namely, reducing the photogenerated electron-hole recombination during photocatalysis and modifying the magnetic properties of MF to become superparamagnetic. The synthesised Re-doped MF was found to be visible light active, as evidenced by the transient photocurrent response and the obtained band gaps, which were in the range of 1.84–1.93 eV. From the cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel polarization plots, it was evident that different RE element dopants have different effects on improving the electrochemical properties of MF. Overall, fast electron transfer of the synthesised materials was found to decrease in the following order: Sm-MF > Dy-MF > Ho-MF > MF > Er-MF > Yb-MF. The g-factor and peak-to-peak line width were found to be in the range of (2.221–2.317) and (93.17–149.85 mT), respectively. The resonance field and hysteresis loop (H c) were found to be in the range of (289.2–301.86 mT) and (8.24–32.61 mT), respectively. Overall, the synthesised RE-doped MF exhibits ferromagnetic properties, and the obtained small H c values hint at these particles exhibiting superparamagnetic properties. In summary, doping MF with Sm, Dy, and Ho is more desirable as it alters the magnetic properties towards superparamagnetic and improves its electrochemical properties. Thus, this study is of importance in advancing the field of photocatalysis in water treatment and material science. • RE (Sm, Dy, Ho, Er, and Yb) were successfully incorporated into the MF spinel structure. • Sm, Dy and Ho dopants improved the electrochemical and optical properties of MF. • The magnetic properties of MF were improved. • The produced photocatalysts were visible light active. [ABSTRACT FROM AUTHOR]

• Effect of dysprosium on properties of extruded Mg–Zr–Sr–Dy is studied. • Significant improvement in mechanical and corrosion properties is achieved. • Dy addition resulted in dynamic recrystallization and evolution of a RE texture. • Formation of Dy 2 O 3 in Mg(OH) 2 protective films improved the corrosion resistance. In this study, extrusion was performed on Mg‒Zr‒Sr‒Dy alloys for improving their mechanical, corrosion, and biocompatibility properties. Effects of extrusion and alloying elements on the microstructural characteristics, tensile and compressive strengths, corrosion behavior, and biocompatibility were investigated. The Mg‒Zr‒Sr‒Dy alloys were composed of an α-Mg matrix containing { 10 1 ¯ 2 } extension twins and secondary phases of intermetallic compounds Mg 17 Sr 2 and Mg 2 Dy. Evolution of basal and rare earth (RE) textures was observed in the extruded alloys and an increase in Dy content to 2 wt.% resulted in texture randomization and strengthening of the RE component, mainly due to particle-stimulated nucleation and a change from discontinuous dynamic recrystallization to continuous dynamic recrystallization, which also led to an improved tension–compression yield asymmetry of 0.87. Extrusion of the alloys significantly enhanced their tensile and compressive properties due to improved distribution of alloying elements and formation of textures. Corrosion rates tested by hydrogen evolution testing, potentiodynamic polarization, and electrical impedance spectroscopy showed similar trends for each composition, and the lowest corrosion rate of 3.37 mmy−1 was observed for the Mg-1Zr-0.5Sr-1Dy in the potentiodynamic polarization testing. Dy 2 O 3 was observed in the inner layers of the Mg(OH) 2 protective films, whose protective efficacy was confirmed by charge-transfer and film resistances. A comparison among the minimum CRs observed in this study and previously studied as-cast Mg‒Zr‒Sr‒Dy and extruded Mg‒Zr‒Sr alloys, demonstrates that both the extrusion process and addition of Dy in Mg‒Zr‒Sr improved the CR. Similarly, extruded Mg–Zr–Sr–Dy alloys showed improved cell viability and adhesion of human osteoblast–like SaOS2 cells due to increased corrosion resistance and enhanced Sr distribution within the Mg matrix. [ABSTRACT FROM AUTHOR]

A number of new isostructural ternary intermetallic compounds of the composition R4Ru2Ga3 (R = Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er) were found in ternary R–Ru–Ga systems. The single-crystal X-ray diffraction study of Nd4Ru2Ga3 showed that this compound crystallizes in the monoclinic system and it is a representative of a new structure type (a = 10 Å, b = 4.0533(11) Å, c = 9.720(3) Å, β = 111.080(7)°, space group С2, Z = 2, R1 = 0.043, wR2 = 0.077 for 1518 reflections). The specific structural feature of this compound is the presence of distorted RuNd6 (AlB2 type) and GaNd8 (CsCl type) units. The shortest Nd–Ru distance in the polyhedron is 2.8463(16) Å, which is significantly smaller than the sum of the corresponding atomic radii. The unit cell parameters and volumes in the R4Ru2Ga3 series (R = Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er) decrease in accordance with lanthanide compression, while their melting points increase. [ABSTRACT FROM AUTHOR]

Using the existing architecture of [Dy(Tp2-py)F]+ that supports a terminal Dy–F bond, the synthesis and isolation of [Dy(Tp2-py)F(THF)2](PF6) and its diamagnetic yttrium analogue have been achieved. Alternating current magnetic susceptibility studies show an increased effective energy barrier of Ueff = 661(6) cm−1 (951(8) K), the highest yet reported for a high coordinate (n > 8) lanthanide single-ion magnet. [ABSTRACT FROM AUTHOR]

Three new hetero-metallic CuII-LnIII complexes [(CuL)Gd(NO3)3(CH3OH)]n (1), [(CuL)Tb(NO3)3(H2O)]· [CuL] (2) and [(CuL)Dy(NO3)3(H2O)]·[CuL] (3) have been synthesized using a mono-nuclear Cu(II) complex, [CuL], of an unsymmetrically di-condensed N2O3 donor Schiff base ligand, N-(3-methoxysalicylidene)-N-(salicylidene)-1,2-ethylenediamine (H2L). Single crystal X-ray crystallography revealed that complex 1 is a nitrate bridged 1D chain of dinuclear Cu(II)-Gd(III) units whereas in 2 and 3, the dinuclear Cu(II)-Ln(III) units are co-crystallized with a [CuL] unit. The Ln(III) centers are nine coordinated with the geometry of a spherical capped square antiprism for Gd and spherical tricapped trigonal prism for Tb and Dy. The geometry of the Cu(II) center is distorted octahedral for complex 1 and distorted square planar for complexes 2 and 3. Temperature-dependent molar magnetic susceptibility measurements in 1-3 revealed the presence of overall ferromagnetic coupling between the Cu(II) and Ln(III) centers. Notably, field induced single-molecule magnet behavior was witnessed in the Tb(III) derivative (2). The ab initio calculations indicated that upon application of an external magnetic field, the tunneling in the ground state of complex 2 gets reduced and thereby field-induced SMM behaviour is observed. Besides, in the case of complex 1, BS-DFT calculations were carried out to gain further insights into the magnetic exchange coupling interactions between the Cu(II) and Gd(III) centers. [ABSTRACT FROM AUTHOR]

Two uranium oxide hydrate frameworks (UOHFs) with either Dy3+ or Lu3+ ions, Dy1.36(H2O)6[(UO2)10UO13(OH)4] (UOHF‐Dy) or Lu2(H2O)8[(UO2)10UO14(OH)3] (UOHF‐Lu), were synthesized hydrothermally and characterized with a range of structural and spectroscopic techniques. Although SEM‐EDS analysis confirmed the same atomic ratio of ~5.5 for U : Dy and U : Lu, they displayed different crystal morphologies, needles for UOHF‐Dy in the orthorhombic C2221 space group and plates for UOHF‐Lu in the triclinic P‐1 space group. Both frameworks are composed of β‐U3O8 type layers linked by pentagonal bipyramidal uranium polyhedra, with the Dy3+/Lu3+ ions inside the channels. However, the arrangements of Dy3+/Lu3+ ions are different, with disordered Dy3+ ions well aligned at the centers of the channels and single Lu3+ ions well‐separated in a zigzag pattern in the channels. While the characteristic vibrational modes were revealed by Raman spectroscopy, the presence of a pentavalent uranium center in UOHF‐Lu was confirmed with diffuse reflectance spectroscopy. The formation of two types of UOHFs with lanthanide ions, high or low symmetry, and the structure trend were discussed regards to synthesis conditions and lanthanide ionic radius. This work highlights the complex chemistry driving the formation of UOHFs with lanthanide ions and has implications to the spent nuclear fuel under geological disposal. [ABSTRACT FROM AUTHOR]

New silanediamide complexes of rare-earth elements are synthesized: [{Dy(Me2Si(NMes)2)(THF)2}2(μ-Cl)2] (Dy1), [{Ln(Me2Si(NMes)2)(THF)2}2(μ-BH4)2] (Ln2, Ln = Y, Dy), and [{Ln(Me2Si(NMes)2)(THF)2}2 (μ-SPh)2] (Ln3, Ln = Y, Tb, Dy), Mes = 2,4,6-(CH3)C6H2=mesityl. The compounds are isolated as crystalline phases Dy1, Ln2 (Ln = Y, Dy), Y3·2THF, Tb3·2C7H8, Dy3·2THF, and Dy3·2C7H8 and characterized by single crystal X-ray diffraction. All complexes have a binuclear structure; a silanediamide ligand is chelated to each Ln atom, and Cl–, , or SPh– act as bridges. By photoluminescence spectroscopy of the solutions of Tb and Dy complexes in THF it is shown that (Me2Si(NMes)2)2– is an effective ligand antenna, which sensitizes metal-centered emission of these lanthanides. [ABSTRACT FROM AUTHOR]

Sandwich d/f heterometallic complexes [(Ln(hfac)3)2M(acac)3] (Ln = La, Pr, Sm, Dy and M = Co; Ln = La and M = Ru) were prepared in strictly anhydrous conditions reacting the formally unsaturated fragment [Ln(hfac)3] and [M(acac)3] in a 2-to-1 molar ratio. These heterometallic complexes are highly sensitive to moisture. Spectroscopic observation revealed that on hydrolysis, these compounds yield dinuclear heterometallic compounds [Ln(hfac)3M(acac)3], prepared here for comparison purposes only. Quantum mechanical calculations supported, on the one hand, the hypothesis on the geometrical arrangement obtained from ATR-IR and NMR spectra and, on the other hand, helped to rationalize the spontaneous hydrolysis reaction. [ABSTRACT FROM AUTHOR]

In this work we report the synthesis, structural characterization and magnetic properties of a family of butterfly complexes {Cr2Ln2} with Ln = Tb (4), Ho (5), Er (6), Tm (7) and Yb (8), extending the family of previously reported isostructural compounds with Gd (1), Dy (2) and Y (3). As in 1 and 2, an anti-ferromagnetic Cr(III)–Ln(III) exchange interaction is found. For oblate ions 4 and 5, SMM behavior with a purely Orbach relaxation mechanism is observed with thermal barriers of 38 cm−1 (4) and 32 cm−1 (5). Complex 4 displays hysteresis opening up to 2.4 K with loss of magnetization at zero field. The prolate complex ions 6 and 7 are field-induced SMM's with dominant Orbach, direct and QTM relaxation mechanisms. Compound 8 did not show SMM properties. [ABSTRACT FROM AUTHOR]

We herein provided a systematical determination of the structural and magnetic properties, especially of the magnetocaloric effect (MCE) and magnetocaloric performances of four rare-earth oxychlorides, i. e., the RE OCl (RE = Ho, Dy, Tb and Gd) compounds. The studied RE OCl compounds are all crystallized in the tetragonal matlockite structure (P 4/ nmm space group) and the RE , O, and Cl elements are with the RE 3+, O2−, and Cl− valence states, respectively. The DyOCl, TbOCl and GdOCl compounds reveal an antiferromagnetic transition at around approximate 9.5, 3.7 and 4.8 K, respectively. The magnetocaloric performances are checked by the maximum magnetic entropy change, relative cooling power, and temperature-averaged entropy change with 5 K lift, which are found to be 14.16 J/kgK, 375.55 J/kg and 13.89 J/kgK for HoOCl, to be 14.88 J/kgK, 488.14 J/kg, and 14.60 J/kgK for DyOCl, to be 14.59 J/kgK, 419.67 J/kg, and 14.42 J/kgK for TbOCl, and to be 16.16 J/kgK, 213.68 J/kg, and 14.39 J/kgK for GdOCl, with the magnetic field change of 0–7 T, respectively. [ABSTRACT FROM AUTHOR]

This paper presents the elastic deformation and thermodynamic theory for crystals with HCP structure on the basis of the statistical moment method (SMM) together with numerical results and discussions for metals Mg, Zn, Dy, Er and Gd. Some numerical results are compared with experiments and other calculations. [ABSTRACT FROM AUTHOR]

We herein investigated four rare earth (RE)-based oxides, the RE 2 SiO 5 (RE = Gd, Dy, Ho, and Er) silicates, regarding their structural and cryogenic magnetic properties. All the RE 2 SiO 5 silicates are found to crystallized in a monoclinic structure. X-ray photoemission spectroscopy spectra illustrate that RE , Si and O elements in RE 2 SiO 5 silicates are present as RE 3+, Si4+, and O2−, respectively. The Dy 2 SiO 5 reveals a first-order magnetic transition around 4.5 K. The magnetic phase transition temperatures are probably below 2 K for the RE 2 SiO 5 (RE = Gd, Ho, and Er) silicates. Large cryogenic magnetocaloric effects (MCE) and good magnetocaloric performances were observed in the RE 2 SiO 5 silicates. The MCE parameters in terms of the maximum magnetic entropy changes, the temperature-averaged entropy change (5 K-lift) and refrigerant capacity under a magnetic field change of 0–5 T are determined to be 35.5, 30.4 J/kgK, and 215.7 J/kg for Gd 2 SiO 5 , to be 13.3, 12.9 J/kgK, and 190.5 J/kg for Dy 2 SiO 5 , to be 15.3, 15.1 J/kgK, and 274.1 J/kg for Ho 2 SiO 5 and to be 17.9, 16.5 J/kgK, and 181.14 J/kg for Er 2 SiO 5 , respectively. These derived values of MCE parameters of the RE 2 SiO 5 silicates, especially for Gd 2 SiO 5 , are at similarly high level with or better than those of the updated candidate materials, making them also of potential for practical magnetic refrigeration applications. [ABSTRACT FROM AUTHOR]

Cryogenic refrigeration technology based on magnetocaloric effects plays a critical role in a variety of technological applications. In this paper, we report the cryogenic magnetocaloric effects of a series of sodium-rare earth fluoride samples (Ln = Gd, Tb, Dy, Ho, Er, Tm, Yb) synthesized by the solid-state reaction method. These compounds all crystallize in a hexagonal crystal structure. Down to 2 K, no magnetic ordering was detected, while all compounds show negative Curie–Weiss temperatures indicative of strong antiferromagnetic coupling. Magnetic fields effectively suppress the magnetic fluctuations, leading to a maximum magnetic entropy change of −56 J kg−1 K−1 in NaGdF4 at the magnetic field change from 0 to 50 kOe. These series of compounds are potentially excellent magnetic refrigerants at low temperatures. [ABSTRACT FROM AUTHOR]

Rare-earth substituted nanocrystalline hexagonal strontium ferrites with chemical formula Sr1 − xPrxFe12O19 (0 ≤ x ≤ 0.1) and Sr0.95Re0.05Fe12O19 (Re = La, Pr, Nd, Dy, Yb), were prepared by sol-gel autocombustion method. The effects of calcination temperature, rare earth ion concentration and rare earth ion radius on the structure and magnetic properties of nano-sized hexagonal strontium ferrites were investigated. X-ray diffraction (XRD) and Vibrating sample magnetometer (VSM) were applied for the systematical investigation of phase composition, crystal structure and magnetic properties of the samples respectively. The suitable calcination temperature of nanocrystalline strontium ferrites was determined to be 900 ℃, which was attributed to the relationship between the calcination temperature and the rotation of the domain wall. The coercivity (Hc) of Sr1 − xPrxFe12O19 reached a maximum at x = 0.05 and the saturation magnetization (Ms) decreased with the increase of Pr substituting content. This reduction followed the spin canting and magnetic dilution which results in the dislocation of super exchange interactions. For Re-substituted samples, the Hc increased with the decreasing ionic radius of substituted elements, while the Ms slightly decreased in comparison to the non- substituted sample. The synthesized samples could be used in permanent magnets, high-density magnetic recording medium, and microwave equipment. [ABSTRACT FROM AUTHOR]

High-entropy rare earth phosphates (HE REPO 4 , RE = Ho, Tm, Yb, Lu, Dy, Er and Y) with xenotime structure have been successfully synthesized and comprehensively characterized to evaluate their feasibility as thermal/environmental barrier coatings (T/EBCs) applied in SiC f /SiC ceramic matrix composites (SiC-CMCs). HE REPO 4 show good chemical compatibility with SiO 2 at 1400 °C and excellent high-temperature stability up to 1750 °C. The thermal expansion coefficient (TEC) of HE (6RE 1/6)PO 4 is 5.9 × 10−6/°C ranging from room temperature to 900 °C, which is close to that of SiC-CMCs. Compared with single-component REPO 4 , the thermal conductivity of HE (6RE 1/6)PO 4 (from 5.1 W·m−1·K−1 at 100 °C to 2.8 W·m−1·K−1 at 1300 °C) is significantly reduced benefiting from larger lattice distortion. These allow HE REPO 4 to be a potential candidate as T/EBCs applied in SiC-CMCs. [ABSTRACT FROM AUTHOR]

High-performance sintered Nd-Pr-Fe-B magnets were successfully prepared by depositing Dy/Tb films on the surface using magnetron sputtering, which resulted in superior grain boundary diffusion (GBD) under heat treatments. The course of the diffusion was assessed using an electron probe microanalyzer (EPMA) and inductively coupled plasma (ICP). The magnetic properties and thermal stability of the magnets before and after diffusion were investigated. The results show that, mainly due to the increased and optimized Nd-Pr-rich phases and the formation of the (Nd,Pr,Dy/Tb)2Fe14B shell structure surrounding the (Nd,Pr)2Fe14B grains, the coercivity of the Dy- and Tb-diffused magnets was enhanced from 16.7 kOe to 24.8 kOe and 28.4 kOe, respectively, while the corresponding maximum energy product (BHmax) was 48.1 MGOe and 48.5 MGOe, respectively. The consumption of Dy/Tb in this work (0.35 wt% Dy in the Dy-diffused magnet and 0.42 wt% Tb in the Tb-diffused magnet) is much lower than that of previously reported magnets with comparable coercivity. Furthermore, Dy- or Tb-diffused magnets exhibit better thermal stability than that of the original magnet, owing to the better resistance to thermal disturbances of the magnets with optimized microstructure. This work can provide useful guidance for preparing Nd-Fe-B magnets with low cost and high performance. [ABSTRACT FROM AUTHOR]

We have systematically studied the crystal structure, cryogenic magnetic properties and MCE in RE 2 MgTiO 6 (RE = Tb, Dy, Ho and Er) DP oxides. The four RE 2 MgTiO 6 samples are all found to crystallize in a monoclinic DP structure (P 2 1 /n space group). The Néel temperature (T N) are found to be 4.7, 4.5, 3.1 and 2.1 K for RE 2 MgTiO 6 (RE = Tb, Dy, Ho and Er) DP oxides, respectively. Moreover, the maximum magnetic entropy change (-Δ S M max) together with relative cooling power (RCP) near T N under a magnetic field change (ΔH) of 0–7 T are evaluted to be 16.85, 360.59 for Tb 2 MgTiO 6 , 17.72, 381.05 for Dy 2 MgTiO 6 , 15.92, 398.14 for Ho 2 MgTiO 6 and 22.95 J/kg K, 459.09 J/kg for Er 2 MgTiO 6 , respectively. The excellent cryogenic MCE suggest that RE 2 MgTiO 6 (RE = Tb, Dy, Ho and Er) DP oxides can be used as a promising candidate material for cryogenic magnetic refrigeration. [ABSTRACT FROM AUTHOR]

The complex formation of the redox-active ligand bis(N,N'-2,6-diisopropylphenyl)-9,10-phenanthrenediimine (DippPDI) with alkaline metal (Li, K) and lanthanide (Sm, Dy) cations is studied. The reduction of DippPDI with an alkaline metal excess affords the dianionic form of the ligand (DippPDA2–), which crystallizes with the potassium cation as the coordination polymer [K2(DippPDA)(Thf)3] (Thf is tetrahydrofuran). The reaction of equimolar amounts of the lithium salt with the dianionic form of the ligand and neutral diimine affords the lithium complex with the radical-anion form (DippPSI•–) crystallized as [Li(DippPSI)(Thf)2]. The samarium(III) complex [SmCp*(DippPDA)(Тhf)] (I) is formed by the reduction of DippPDI with samarocene [Sm (Thf)2] (Cp* is pentamethylcyclopentadienide): both the samarium(II) cation and Cp*– anion are oxidized in the reaction. DippPDI does not react with similar ytterbocene. The dysprosium(III) complexes are synthesized by the ion exchange reactions between DyI3(Thf)3.5 and potassium or lithium salt with the DippPDA2– dianion. Similar complexes [Dy(DippPDA)I(Thf)2] (IIThf) and [Dy(DippPDA)I(Thf)(Et2O)] () are formed in the reactions with the potassium salt depending on the solvent used: a THF–hexane or a diethyl ether–n-hexane mixture, respectively. The coordination of the dysprosium cation by the π system of the conjugated fragment of the NCCN ligand is observed in IIThf, whereas in this coordination is absent. The reaction with Li2(DippPDA) affords the binary complex salt [Li(Тhf)3(Et2O)][DyI2(DippPDA)(Тhf)] (III, crystallization from a THF–Et2O mixture). The crystallization from THF gives the [Li(Тhf)4][DyI2(DippPDA)(Thf)] salt (III') containing the same anion as III. The structures of all new complexes are studied by X-ray diffraction (XRD, CIF files CCDC nos. 2260307–2260313). [ABSTRACT FROM AUTHOR]

The effect of ionic radii sizes on magnetostriction is studied in relation to structural and magnetic properties. To explore the effect of the chemical pressure, nanoparticles of rare‐earth (RE) orthoferrites, SmFeO3, DyFeO3, HoFeO3, and LuFeO3 are studied using X‐ray diffraction, field emission scanning electron microscopy, and Raman spectroscopy. Magnetic and magnetostriction measurements are also performed. In these orthoferrites, the coordination of the RE ion is eightfold, whereas the RE ionic radii are significantly different, which directly influences the structural parameters. The distortion of FeO6 octahedra is observed as a result of changing chemical pressure within the lattice. The different magnitudes of magnetostriction in RE orthoferrites can be attributed to the different degrees of distortion of FeO6 octahedra, R–O dynamics, and spin–orbit interactions in the system. The maximum value of magnetostriction (∼ 19 ppm) and magnetization at 2 K (30.64 emu/g) is demonstrated by HoFeO3. Comparison of structural parameters of the samples to their respective bulk counterparts indicated relative structural distortion in nanoparticles. [ABSTRACT FROM AUTHOR]

To study the effect of diamagnetic ions on magnetic interactions, utilizing a compartmental ligand (Z)-2-(hydroxymethyl)-4-methyl-6-((quinolin-8-ylimino)methyl)phenol (LH2), two different series of ZnII–LnIII complexes, namely the trinuclear series of [DyZn2(L)2(μ2-OAc)2(CH3OH)2]·NO3·MeOH (1), [TbZn2(L)2(μ2-OAc)2(CH3OH)2]·NO3·5MeOH·H2O (2), and [GdZn2(L)2(μ2-OAc)2(CH3OH)2]·NO3·MeOH·CHCl3 (3) and the tetranuclear series of [Dy2Zn2(LH)4(NO3)4(μ2OAc)]·NO3·MeOH·H2O (4), [Tb2Zn2(LH)4(NO3)4(μ2-OAc)]·NO3·MeOH·2H2O (5), and [Gd2Zn2(LH)4(NO3)4(μ2-OAc)]·NO3·MeOH·2H2O (6), were synthesized. Trinuclear ZnII–LnIII complexes 1–3 consist of one LnIII ion sandwiched between two peripheral ZnII ions forming a bent type ZnII–DyIII–ZnII array with an angle of 110.64°. Tetranuclear ZnII–LnIII complexes 4–6 are basically a combination of two dinuclear moieties of [LnZn(LH)2(NO3)2]+ connected by one bidentate bridging acetate ion in μ2-OAc coordination mode. The detailed magnetic analysis reveals that complexes 1 and 4 are single molecule magnets having energy barriers of 34.98 K and 46.71 K with relaxation times (τ0) of 5.05 × 10−4 s and 5.24 × 10−4 s, respectively. Ab initio calculations were employed to analyze the magnetic anisotropy and magnetic exchange interaction between the ZnII and LnIII centers with the aim of gaining better insights into the magnetic dynamics of complexes 1–6. [ABSTRACT FROM AUTHOR]

Five decanuclear lanthanide–iron clusters, formulated as [Ln2Fe8(hmp)10(μ2-OH)4(μ3-OH)2(μ4-O)4(H2O)6]·6ClO4·xH2O (x ≈ 8, Ln = Y for 1; x ≈ 6, Ln = Dy for 2; x ≈ 6, Ln = Ho for 3; x ≈ 7, Ln = Tb for 4; x ≈ 7, Ln = Gd for 5, Hhmp = 2-(hydroxymethyl)pyridine), have been synthesized and structurally characterized. Single-crystal structural analysis reveals that the cluster consists of six face-sharing defective cubane units. Dynamic magnetic investigations indicated that cluster 2 exhibits single-molecule magnet behavior under a zero dc field eliciting an effective energy barrier of Ueff = 17.76 K and a pre-exponential factor of τ0 = 7.93 × 10−8 s. Investigation of the performance of a series of FeIII–DyIII SMMs indicates that the relatively low energy barrier in 2 is associated with the weak ferromagnetic coupling between FeIII and DyIII ions, while the strength of ferromagnetic interaction in these clusters is mainly related to the bond distances between DyIII and O atoms coordinated to FeIII ions. Clusters 3 and 4 exhibit similar dual relaxation pathways under their respective optimal external applied dc field, where the direct relaxation process occurs in the low-frequency area, which impedes the extraction of the Ueff, while the secondary relaxation process appears at a higher frequency, which is probably a connection with intermolecularly driven relaxation. Our findings offer a magneto-structural correlation model for further investigating the single-molecule magnet behavior in lanthanide–iron systems. [ABSTRACT FROM AUTHOR]

To investigate novel glass materials applicable to W-LED, we designed and prepared a series of glasses with varying compositions. The compositions of the glasses were (64-x)B 2 O 3 –15Al 2 O 3 –10Na 2 O–10Bi 2 O 3 -xCaF 2 -0.5Dy 2 O 3 -0.5Eu 2 O 3 (x = 0, 5, 10, 15, 20, 25). The glasses were synthesized using the melting quenching method. The effect of CaF 2 on the structural feature of fluoroborate glass was studied by infrared spectroscopy analyses. Determination of fluorine content in glass by 19F NMR inversion spectroscopy. The absorbance of glass increased as the CaF 2 content increased in the visible and ultraviolet light ranges. The optical band gap of the prepared glasses was obtained from the absorption spectrum, which confirmed the existence of nonbridging oxygen (NBO) in the glass network structure. The fluorescence lifetime of the glass increases with increasing CaF 2 content, and the quantum yield of the glass first increases and then decreases. In addition, fluoroborate glass had a lower Urbach energy, indicating that its network structure was relatively uniform and stable. In contrast, the increase in Urbach energy is due to the substitution of CaF 2 , leading to more defects. By adjusting the excitation wavelength and CaF 2 content, the color temperature (1598–3346 K) and color rendering index (36–63) of fluoroborate glass can be effectively adjusted. These results show that the prepared Dy/Eu co-doped fluoroborate glasses have a potential application in white lighting. [ABSTRACT FROM AUTHOR]

R5Pd2 compounds are known to exhibit magnetic glass transition and large cooling power in the cryogenic temperature region. All the R5Pd2 (R = Ho, Dy, Dy0.6Gd0.4) compounds crystallize in the cubic Dy5Pd2-type of structure (space group Fd3m). The compounds Ho5Pd2, Dy5Pd2, and (Dy0.6Gd0.4)5Pd2 undergo a paramagnetic to glass transition at 27 K, 38 K, and 58.5 K with a small hump at 10 K, 14 K, and 20 K respectively, confirming the double glass transitions present in these compounds. The maximum isothermal magnetic entropy changes (− ΔSmax) for the compounds Ho5Pd2, Dy5Pd2, and (Dy0.6Gd0.4)5Pd2 are 19.95 J/kg-K, 7.89 J/kg-K, and 7.4 J/kg-K with RCP values 987 J/kg, 549 J/kg, and 673 J/kg respectively for magnetic field change of 70 kOe. However, there is a controversy regarding the order of magnetic phase transition present in these compounds. A detailed investigation on the order of magnetic phase transition in Ho5Pd2, Dy5Pd2, and (Dy0.6Gd0.4)5Pd2 compounds has been studied. Heat capacity measurements give a fingerprint of the absence of first-order magnetic phase transitions in these compounds. Field dependent magnetic entropy change studies on these compounds confirm the second-order nature of magnetic phase transitions. [ABSTRACT FROM AUTHOR]

The reaction of UO2 with the respective lanthanide metal and purified graphite in an arc-melting furnace led to the formation of solid solutions of the composition LnxU1−xC2, with Ln = Tb, Dy, Ho, Tm, and Lu. They all crystallize in the tetragonal CaC2 type structure (I4/mmm, Z = 2). Elemental analyses of selected samples (EDX) confirm that the composition of the resulting solid solution is in reasonable agreement with the nominal (weighed-in) composition of the starting materials, i.e., a significant evaporation of the lanthanide metals during the arc-melting synthesis does not occur. The lattice parameters of the solid solutions were extracted using Le Bail fits of high-resolution synchrotron powder diffraction data (beamline P02.1, DESY, Hamburg, Germany; beamline BL 09, DELTA, Dortmund, Germany), revealing ideal Vegard behavior for all five solid solutions. XANES investigations on all compounds at the Ln-LIII and U-LIII edges reveal that the occupancies of the U-6d orbitals decrease with increasing x, whereas the occupancies of the Ln-5d orbitals increase, pointing to an electron transfer from the uranium to the lanthanide cations. Examination of the shifts of the absorption edge (E0) leads to the same finding. [ABSTRACT FROM AUTHOR]

A series of spectrally tunable Dy3+/Eu3+-coactivated double perovskites SrLaLiTeO 6 (SLLT) were synthesized via solid-state ceramic route under air condition. Considering differences of ionic radius and valences among the dopants and host cations, Dy3+/Eu3+ are all inclined to enter La site, though slight occupations in Sr site cannot be completely ruled out. Dy shows narrow band emissions in blue (B) to yellow (Y) region, which is stemmed from magnetic (4F 9/2 → 6H 15/2) and electric (4F 9/2 → 6H 13/2) dipole transitions, respectively. Eu3+ exhibits orange-red (O–R) emissions, with two dominant peaks located at ∼ 593 and 617 nm from magnetic (5D 0 → 7F 1) and electric (5D 0 → 7F 2) dipole transitions, which could be used as compensation for the red-emitting portion in pc- w LEDs via energy transfer (ET) from Dy to Eu to overcome the disadvantage of low excitation efficiency. The substitutional local site symmetry could be regularly modified along with severely impacting on Y/B and R/O ratios for Dy and Eu emission colors via simply modifying the doping contents, due to changes in bond lengths and Coulomb potentials from interconnected octahedrons [LiO 6 ] and [TeO 6 ] around the dopants. The fabricated pc- w LED via combining a commercial n -UV LED chip with the SLLT: Dy/Eu, exhibited splendid EL performance, with the CIE coordinate is calculated to be (0.3690, 0.3539), CCT of 3232 K, and CRI (R a) of 86.5. Altogether, it manifests that the stable SLLT: Eu and SLLT: Dy/Eu are potentially good candidates for applications as red and white phosphors, respectively in indoor plant growth LED and pc- w LEDs. • Dy/Eu is more inclined to enter La site determined via Rietveld, Raman and FTIR tests. • ET mechanism belonged to the d-d interaction is detailed studied via spectral analysis. • Local site symmetry is successfully modulated via simply changing in concentration of dopants. • PL from SLLT: Dy/Eu cold be well tunned via both the ET and local site symmetry. • Warm white light via the ' n -UV LED + codoped white emitting phosphor' is achieved. [ABSTRACT FROM AUTHOR]

Large single crystals of rare-earth calcium oxoborates R Ca 4 O (BO 3) 3 with R = Er , Y, Dy, Gd, Sm, Nd, La (R C O B) were grown by the Czochralski method. Complete sets of dielectric, piezoelectric stress, and elastic stiffness coefficients of the R C O B crystal species were determined at ambient conditions using a combination of resonant ultrasound spectroscopy and the substitution method. The results are inherently consistent and reveal clear crystal chemical trends, with the size of the trivalent cation playing an important role. In particular, the longitudinal and shear aggregate elastic stiffnesses, c 11 iso and c 44 iso , decrease from about 165 to 154 GPa and, respectively, 45 to 41 GPa from the smallest to the largest R 3 + cation of the investigated crystal species, while the dielectric coefficients ϵ 22 and ϵ 33 increase. However, the maximum longitudinal piezoelectric effect peaks with 8.6 pCN − 1 at N d C O B , the species where the radius of R 3 + best matches the one of Ca 2 + . Increasing differences in the size of R 3 + and Ca 2 + lead to anisotropic stresses in the crystal lattice, which are partially relaxed by an increasing degree of cation disorder. [ABSTRACT FROM AUTHOR]

In composite magnets, an in-depth understanding of magnetization reversal behaviors promotes optimizing the structure design of a magnet and improving its performance. In this work, the perpendicular magnetic anisotropic Ta/La–Pr–Fe–B/Dy/La–Pr–Fe–B/Ta multilayers have been prepared by adjusting the thickness of the Dy layer. The domain reversal evolutionary procedure has been investigated in different aspects including the characterization of domain morphology, micromagnetic analysis, and irreversible reversal distribution. It is confirmed that the nucleation mechanism is dominant in determining the coercivity of the multilayers with Dy diffusion. Dy diffusion helps to enhance the coercivity of the multilayers. The formation of Dy-containing hard magnetic phases and rare-earth-rich grain boundary phases by adding the Dy element leads to a strong nucleation field and isolation of hard magnetic phase grains, respectively. Our results aid in the understanding of magnetization reversal behaviors and enhance the magnetic properties of highly abundant rare-earth permanent magnetic multilayer films with the doping element. [ABSTRACT FROM AUTHOR]

Rare earth element (REE) permanent magnets (NdFeB) are a critical element in a vast and growing number of industrial applications. In consumer electronics, a broad category encompassing computer, CD, and DVD hard drives, in addition to the ubiquitous cell phones, the nominal NdFeB magnet content may be small, but the global market share for this sector accounts for almost 30% of NdFeB demand, due to a large and continually increasing consumer base. It is estimated that wind turbines that primarily employ permanent magnets will add roughly 110 GW annually of on- and off-shore capability over the next few years. Electric vehicles (EVs) and E-bicycles (EBs) equipped with permanent magnet motors comprise the transportation contribution. Permanent magnet motors have garnered nearly 100% of the market share among EV manufacturers worldwide. Industrial, professional service, and personal robots, most using permanent magnets, are also included in the projected global need for rare earths, particularly Nd and Dy. The sector projects significant growth of approximately 10% across robotic categories. In this paper, we calculate the future demand for Nd and Dy through 2050 across these sectors using a compounded annual growth rate coupled with magnet weight and rare earth content. Uncertainties in the estimates, such as the true global production of Nd, a range of end-product scales and/or unit types in each sector, varied magnet compositions, and the variety of uses within a sector, are all considered. [ABSTRACT FROM AUTHOR]

Two sets of 1D/2D lanthanide coordination polymers with formulas of Ln(oqa)3·2H2O [Hoqa = 2-(4-oxoquinolin-1(4H)-yl) acetic acid, Ln = Dy (1), Yb (2)] and Ln(oaa)2(HCOO)(H2O) [Hoaa = 2-(9-oxoacridin-10(9H)-yl) acetic acid, Ln = Dy (3), Yb (4)] have been synthesized and their physical properties were investigated. All four complexes are constructed from seven-coordinate lanthanide ions and corresponding organic linkers. The lanthanide ions in 1 and 2 adopt a pentagonal bipyramid coordination geometry, whereas the coordination geometry of lanthanide ions in 3 and 4 can be described as a capped octahedron. Slow magnetic relaxation behaviors were observed in these four products at a zero/non-zero static magnetic field. Complexes 1, 2 and 4 exhibit the characteristic emission of Ln(III) ions, whereas complex 3 shows ligand-based emission. Bright yellow light emission was also observed when a voltage was applied, demonstrating the potential of 1 for application in light-emitting diodes (LEDs). Compounds 3 and 4 are the first examples of lanthanide complexes based on Hoaa ligands. [ABSTRACT FROM AUTHOR]

Thermodynamic databases are essential to understanding alloy properties and guiding materials design. In this work, the mixing enthalpies of the liquid phase in the Gd-Te, Dy-Te and Ho-Te binary systems are calculated using Ab-initio Molecular Dynamics (AIMD) simulations and the thermodynamic parameters are determined using the CALculation of PHAse Diagrams (CALPHAD) method combined with the phase equilibrium data and thermodynamic data. The associated solution model is employed to describe the liquid phase of these systems. The sublattice model (Gd,Te)0.0296(Gd)0.4(Te)0.5714, (Dy,Te)0.0286(Dy)0.4286(Te)0.5714 and (Ho,Te)0.5(Te)0.5 are utilized to describe Gd2Te3, Dy2Te3 and HoTe, respectively. The line compounds, i.e. GdTe, DyTe, and DyTe2, are modeled using the stoichiometric model. The calculated results can describe the experimental and thermodynamic information reported in the literature. In addition, the existence of a liquid-liquid separation in the Dy-rich side in the Dy-Te binary system is proposed in this work. [ABSTRACT FROM AUTHOR]

Kaolinite is one of the principal rare earth element (REE) ion-adsorption clays that hosts a wide range of elements, including Dy(III) as a representative example. Ammonium sulfate is a typical salt used to leach REEs. Due to the carbon dioxide emissions which occur during ammonia production, it is urgently necessary to develop low environmental pollution leaching agents that can replace (NH4)2SO4. MgSO4 is regarded as the most promising eco-friendly leaching agent. Herein, the first-principles plane-wave pseudopotential method based on the density functional theory (DFT) was used to investigate the stable adsorption structures of Dy(III) and its hydrated ions, MgSO4 leaching agent ions and the corresponding hydrated ions on the surface of kaolinite, which revealed the adsorption mechanism of Dy(III), Mg(II), and SO42− on the silico–oxygen plane and the aluminum–hydroxyl plane of kaolinite. Based on the research results of the steric hindrance effect of Dy(III) on the silico–oxygen plane and the aluminum–hydroxyl plane of kaolinite, the adsorption of Dy(H2O)103+ was more stable on the silico–oxygen plane. It was easier to leach out Dy(III) with MgSO4, while SO42− tended to interact with the rare earth ions in an aqueous solution. The results provide theoretical guidance for efficient rare earth extraction and obtaining novel efficient leaching agents. [ABSTRACT FROM AUTHOR]

Dysprosium (Dy) is considered an important Rare Earth Element (REE) material in modern technology. However, due to its analogous chemical properties to other REEs, differentiating it within mixtures proves to be a challenging endeavor. Voltammetry has emerged as an alternative method for Dy determination, offering heightened sensitivity and fast analysis time. The selection of acetonitrile as the solvent is based on its broad potential range and exceptional conductivity. Additionally, the pursuit of optimal conditions through experimental design plays a pivotal role in identifying specific targets within mixtures. The combination of these methods is assumed to provide a satisfactory detection result. In this study, the Steepest Ascent and Box-Behnken designs were employed to optimize the conditions for Dy determination. The parameters subject to optimization included deposition potential, deposition time, and amplitude modulation. The outcome of this optimization process revealed the optimal conditions for Dy measurement via differential pulse voltammetry which are a deposition potential of -1.5171 V, deposition time of 76.0898 s, and amplitude modulation of 0.0860 V. Under these optimum conditions, the determination of Dy yielded a recovery rate of 99.47%, an accuracy of 97.06%, and a precision of 95.19%. Furthermore, the detection limit and quantitation limit values were found to be 2.1223 mg/L and 7.0744 mg/L, respectively. Moreover, the qualitative voltammetry result provides an insight into distinguishing Dy from Eu in the mixture. [ABSTRACT FROM AUTHOR]

Atomic data are fundamental for plasma diagnostics in laboratory and astrophysics through spectroscopy. These data are extensively present in data bases for light elements, however incomplete for high-mass atoms. This paper presents the results of systematic spectroscopy of 17 elements with high Z , expected to be produced in kilonova events generated by neutron star mergers, whose spectral lines are not yet fully identified in stellar spectra and fusion devices. Experimental data are from échelle high-resolution (λ/Δλ = 60 000) spectroscopy of hollow cathode lamps obtained with the Catania Astrophysical Observatory Spectropolarimeter covering the 3700–10 000 Å range in a single exposure. A total of about 7700 spectral lines with energy level classification not previously listed in the NIST, Kurucz, and VALD data bases are here reported for neutral and singly ionized atomic transitions. For the spectral lines of any species, we report the measured wavelengths and their relative intensities. If possible, we also estimate the transition probabilities under the assumptions of optically thin emission and electric-dipole transitions. These are converted into oscillator strengths ready to be inserted in astrophysical data bases for spectral synthesis. [ABSTRACT FROM AUTHOR]

The hot spot extraction agent N,N,N′,N′-tetraoctyl-3-oxoglutaramide (TODGA) has the advantages of novelty, high efficiency and environmental protection in the separation of rare earths by tandem extraction. In this paper, the characteristic parameters for the separation of dysprosium, erbium, thulium and ytterbium ions in the TOGDA–kerosene/hydrochloric acid system for tandem extraction were calculated. Using a 10% TODGA–kerosene/5 mol·L−1 hydrochloric acid extraction system, the mixture containing Dy3+ 0.258 mol·L−1, Er3+ 0.252 mol·L−1, Tm3+ 0.248 mol·L−1 and Yb3+ 0.242 mol·L−1 can be separated by three separation steps, and four products of Dy3+, Er3+, Tm3+ and Yb3+ can be obtained. The purity of the four products was 99.80%, 99.20%, 99.70% and 99.70%, and the yields were 99.03%, 98.97%, 97.88% and 96.98%, in order. In this paper, the reasons were analyzed for the differences in the ability of the TODGA system to extract heavy rare earth ions (REEs) in terms of density functionality, complex structure and bond valence model. These will provide more basic data and guidance for the industrial application of TODGA. [ABSTRACT FROM AUTHOR]

Fluorine-containing rare earth compounds of the LiLn4Mo3O15F (Ln = Eu, Gd, or Dy) composition have been obtained using solid-phase synthesis in vacuum-sealed quartz ampoules. It was found that only LiEu4Mo3O15F samples are isostructural to cubic Ln5Mo3O16 (Ln = La–Gd) molybdates with a fluorite-like structure. Luminescence, hygroscopic, and electrophysical characteristics of the LiEu4Mo3O15F phase were studied for the first time. The double replacement of europium with lithium and oxygen with fluorine leads to the appearance of a reversible phase transition accompanied by a jump in conductivity by 2 orders of magnitude. The conductivity of the LiEu4Mo3O15F compound exceeds the value of 10−2 S cm−1 at 700 °C. A relationship between the size of the Ln cation and the hygroscopic and conductive properties of LiLn4Mo3O15F compounds has been established: as the lanthanide radius decreases, the compounds lose their ability to absorb water and transfer protons. [ABSTRACT FROM AUTHOR]

In this study, we investigated the structures of lanthanide (Eu(III), Dy(III), and Gd(III)) complexes with p-coumaric (p-CAH2) and caffeic (CFAH3) acids using the FTIRKBr, FTIRATR, and Raman spectroscopic methods. The compositions of the solid phase caffeinates and p-coumarates were obtained on the basis of the amounts of hydrogen and carbon determined using an elemental analysis. The degree of hydration and the thermal decomposition of each compound were examined via a thermal analysis of TG, DTG, and DSC. Antioxidant spectroscopic tests were performed using the DPPH (1,1-diphenyl-2-picrylhydrazyl radical), FRAP (ferric reducing antioxidant activity), and ABTS (2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (diammonium salt radical cation) methods. The antimicrobial activity of each compound against Escherichia coli, Bacillus subtilis, and Candida albicans was investigated. The electrical properties of the liposomes which mimicked the microbial surfaces formed in the electrolyte containing the tested compounds were also investigated. The above biological properties of the obtained complexes were compared with the activities of p-CAH2 and CFAH3. The obtained data suggest that lanthanide complexes are much more thermally stable and have higher antimicrobial and antioxidant properties than the ligands (with the exception of CFAH3 in the case of antioxidant activity tests). The Gd(III) complexes revealed the highest biological activity among the studied lanthanide complexes. [ABSTRACT FROM AUTHOR]

Twenty five new ternary Laves phases RET4Mg and RET4Cd (RE = rare earth element; T = Co, Ni, Cu, Pt) have been synthesized from the elements using niobium or tantalum tubes as inert crucible materials. The lattice parameters have been derived from powder X-ray diffraction data. The structures of Ce1.41(1)Co4Mg0.59(1), Dy1.10(1)Co4Mg0.90(1), LaPt4Cd, Y1.10(1)Cu4Cd0.90(1), Ca0.93(1)Cd0.07(1)Pd2 and Eu0.87(2)Cd0.13(2)Pd2 were refined from single-crystal X-ray diffractometer data. Most phases show certain degrees of RE/Mg or RE/Cd disorder. The quenched phases are assigned to the MgCu2 structure, while the annealed ones adopt the MgCu4Sn type, a translationengleiche superstructure variant of the aristotype. The annealing time has a substantial influence on the degree of ordering and is expressed in the lattice parameters, i.e. larger ones for the disordered samples. The REPt4Cd (RE = La–Nd) samples have been characterized with respect to their magnetic properties. LaPt4Cd is a diamagnet, while CePt4Cd (2.23(1) µB), PrPt4Cd (3.40(1) µB) and NdPt4Cd (3.43(1) µB) are Curie–Weiss paramagnets. The cerium compound shows a slight moment reduction. NdPt4Cd is ordered ferromagnetically at TC = 4.4(1) K. [ABSTRACT FROM AUTHOR]

Due to comparable ionic radii, lanthanoids are known to have similar physical and chemical properties. Separation of lanthanoids from one another is therefore a challenging task. Such crucial separation chemistry could be performed with the help of solvent extraction technique. In order to overcome the associated problems based on solvent extractions, the emulsion liquid membrane based method has been applied to do the selective and efficient extraction of the lanthanoid Dy. This work describes the role of emulsion liquid membranes for the selective extraction of Dy(III) ion with the help of aniline yellow dye at pH 3 medium. The emulsion was prepared using different oils viz, mustard oil, coconut oil and palm oil as the organic phase. The complexation of the lanthanoids (La(III), Ce(III), Ce(IV), Pr(III), Gd(III), Sm(III) and Dy(III)) with aniline yellow (AY) and benzene azo naphthylamine (BAN) dye was studied using UV-Vis spectrophotometer at three different pH (pH 1, pH 3 and pH 5) conditions. The complexation was observed at pH 3 and 5 for only Pr(III) and Dy(III) with both the dyes having high association constant values (∼106 M-1). The emulsion liquid membrane (ELM) prepared with mustard oil, coconut oil and palm oil at pH 3 showed zeta potential value − 30.60 mV, − 27.00 mV and − 35.90 mV respectively. Selective extraction of the Dy-AY complex was obtained for the ELM prepared with mustard oil at pH 3 medium (90%). After extraction of the Dy-AY complex, the zeta potential decreased to − 41.80 mV for the ELM. The effect of stirring time, pH of the medium and the concentrations of the feed solutions have positive correlations towards the extraction process. After the extraction process, the oil reach phase was demulsified using a mixture of organic solvents and the extracted metal ion was back-extracted with the help of cation exchange resin. 88% of the extracted Dy could be back extracted upon demulsification. • Selective extraction of Dy(III) from other lanthanoides was performed using emulsion liquid membrane. • Aniline yellow and benzene azo napthylamine dye were used for the extraction study. • Mustard oil, coconut oil and palm oil were used as membrane phase during extraction of lanthanoides. • ∼90% extraction of Dy(III) was achieved in presence of aniline yellow and mustard oil as membrane phase. • A decrease in zeta potential of the emulsion was observed upon extraction of Dy-aniline yellow complex. [ABSTRACT FROM AUTHOR]

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Tb3Scx Al5-xO12 (TSAG) crystal is a magneto optical crystal material with excellent performance. Solving the cracking problem during the growth of large-sized TSAG crystal is of great significance for its application in high-power magneto-optical isolators. The segregation law of Dy and Lu during the crystal growth process with Czochralski method was investigated, and the effect of Dy and Lu doping on the crystal properties TSAG were also clarified. The results indicate that Dy and Lu doping are helpful to solve the cracking problem of large-sized TSAG crystal. The obtained TSAG crystals have good internal quality, and the resulting extinction ratios are all greater than 33 dB. Lu doping improves the Verde constant of TSAG crystals, while Dy doping has no significant effect on the Verde constant of TSAG crystals. The magneto-optical properties of Dy and Lu co-doped TSAG crystals are basically similar to those of TSAG, and the prepared crystals meet the requirements for high-power laser isolators. [ABSTRACT FROM AUTHOR]

Sm3+ doped and RE3+ (RE = Dy, Er, Gd, La, Nd, Tb)-co-doped CaB6O10 phosphors were prepared at 800°C by the solid-state reaction method. The obtained powders were structurally characterized by X-ray diffraction and Fourier transform infrared analyses. The influences of co-doping rare earth ions on their luminescent properties were also investigated. The emission spectra of the CaB6O10:Sm3+ phosphors consisted of some sharp emission peaks of Sm3+ ions centered at 561, 601, 649, and 708 nm, generating bright orange–red light. The concentration quenching occurred when x equals 0.05 for CaB6O10:xSm3+ phosphor. No remarkable differences were found from excitation spectra of co-doped phosphors CaB6O10:Sm3+, RE3+ in contrast with that of phosphor CaB6O10:Sm3+. The introduction of charge compensator RE3+ (RE = Dy, Er, Gd, La, Nd, Tb) into the host reduced the luminescence intensity of the CaB6O10:Sm3+ phosphors. [ABSTRACT FROM AUTHOR]

A series of 16 mol% CeO 2 -2 mol% Re 2 O 3 co-stabilised zirconia (ZrO 2) (16Ce4ReSZ, Re Eu, Gd, Dy, Y, Er, Yb) ceramic materials were synthesised using a chemical coprecipitation– high-temperature roasting method. Their phase structure, high-temperature phase stability, mechanical properties, thermal conductivity and coefficient of thermal expansion (CTE) were investigated. The results show that the ZrO 2 tetragonal phase co-stabilised by CeO 2 and Re3+ with a smaller radius has better stability. The 16Ce4ReSZ (Re Dy, Y, Er, Yb) materials have high fracture toughnesses, low thermal conductivities, and high CTE values. As the radius of the Re3+ ions decreases, the lattice energy increased, while the lattice distortion decreases, the CTE decreases slightly and the thermal conductivity of the material increases slightly. Owing to the high phase stability of 16Ce4YbSZ, its mechanical properties are best after 100 h of sintering at 1400 °C. [ABSTRACT FROM AUTHOR]

The superconducting transition temperatures (T c ) of RbGd 2 Fe 4 As 4 O 2 , RbTb 2 Fe 4 As 4 O 2 , and RbDy 2 Fe 4 As 4 O 2 are 35 K, 34.7 K, and 34.3 K without doping, respectively. For the first time, we have studied the high-temperature nonmagnetic state and the low-temperature magnetic ground state of 12442 materials, RbTb 2 Fe 4 As 4 O 2 and RbDy 2 Fe 4 As 4 O 2 , using first principles calculations and comparing them with RbGd 2 Fe 4 As 4 O 2 . We also performed a detailed study of the effects of lanthanides and bilayer Fe 2 As 2 . We predict that the ground state of RbLn 2 Fe 4 As 4 O 2 (Ln = Gd, Tb, and Dy) is spin-density-wave-type, in-plane, striped antiferromagnets, and the magnetic moment around each Fe atom is about 2 μ B . We also found that the structural differences caused by the simple ionic radius have little effect on the properties of these three materials. Different lanthanide elements themselves play a major role in the electronic properties of the materials. It can be confirmed that the effect of Gd on RbLn 2 Fe 4 As 4 O 2 is indeed different from that of Tb and Dy, and the presence of Gd is more conducive to interlayer electron transfer. This means that Gd can transfer more electrons from the GdO layer to the FeAs layer compared to Tb and Dy. Therefore, RbGd 2 Fe 4 As 4 O 2 has a stronger internal coupling strength of the bilayer Fe 2 As 2 layer. This can explain why the T c of RbGd 2 Fe 4 As 4 O 2 is slightly higher than that of RbTb 2 Fe 4 As 4 O 2 and RbDy 2 Fe 4 As 4 O 2 . [ABSTRACT FROM AUTHOR]

Using the heavy rare earth Dy element to improve coercivity is the most common solution for hindering the reduction in magnetic properties in the Nd–Fe–B magnet, and the effective utilization of Dy has become the focus of research in industrial society. In this work, we investigated the influence of DyHx addition and diffusion methods on the microstructure, magnetic performance, and thermal stability of the Nd–Y–Fe–B magnet with a Y-rich core structure. The coercivity of the DyHx addition magnet increases from 9.45 kOe to 15.51 kOe when adding 1.6 wt.% DyHx, while the DyHx diffusion magnet increases to 15.15 kOe. According to the analysis of the microstructure and elemental distribution, both Dy-rich shells were basically formed due to the diffusion process of Dy atoms. The Dy-rich shell in the DyHx addition magnet was similar with the original core–shell structure in the Nd–Y–Fe–B magnet. However, the distinct dual-shell structure consisting of a thinner Dy-rich shell and a Y-lean shell was constructed in the DyHx diffused magnet, contributing to the superior coercivity increment and Dy utilization efficiency. Furthermore, the remanence of the DyHx diffused magnet is up to 12.90 kG, which is better than that of the DyHx addition magnet (12.59 kG), due to fewer Dy atoms entering the 2:14:1 matrix grain to cause the antiferromagnetic coupling with Fe atoms. Additionally, the thermal stability of the DyHx diffusion magnet is also better than that of the DyHx addition magnet, owing to the elevated coercivity at room temperature, which expands the application range of the Nd–Y–Fe–B magnet to a certain extent. [ABSTRACT FROM AUTHOR]

Rare earth nickelates (RNOs) have been extensively studied in recent decades because of the metal–insulator phase transition, which can be driven by chemical doping. In the present study, we apply the first-principles calculation to investigate the electronic structures, optical properties, and migration behaviors of Li-doped RNO. Results show that when the doping ratio reaches 100%, RNO changes from the metallic state into an insulating state, which is confirmed by the experimental report. Regarding the optical properties, the absorption coefficient and reflectivity decrease in Li-doped RNO over the entire range of visible and infrared light compared with pristine systems. The migration of Li along the [001] direction of RNO is studied and shows that as the radius of rare earth atoms decreases, the migration barrier generally shows a gradually decreasing trend. These findings may shed light on the application of RNO in electrochromic devices. [ABSTRACT FROM AUTHOR]