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Thermoelectric devices are both solid-state heat pumps and energy generators. Having a reversible process without moving parts is of high importance for applications in remote locations or under extreme conditions. Yet, most thermoelectric devices have a rather limited energy conversion efficiency due to the natural competition between high electrical conductivity and low thermal conductivity, both being essential conditions for achieving a high energy conversion efficiency. Heavy-fermion compounds YbT2Zn20 (T = Co, Rh, Ir) have been reported to be potential candidate materials for thermoelectric applications at low temperatures. Motivated by this result, we applied chemical substitution studies on the transition metal site in order to optimize the charge carrier concentration as well as promote more efficient phonon scatterings. Here, we present the latest investigation on the Ni-doped specimens YbCo2−xNixZn20, where enhanced thermoelectric figure of merit values have been obtained. [ABSTRACT FROM AUTHOR]

As devices become ever smaller and more efficient, the crystallochemically controlled synthesis of high‐performance materials that comprise their core has attracted enormous attention. Integration of complex functional materials into the next generation of electronic devices will require exquisite control of anisotropic form, either as nanotubes, nanotapes, or nanowires, yet the easy preparation of abundant quantities of them remains stubbornly challenging. Herein, a template‐free, flux‐mediated growth of vast quantities of three compositions of phase‐pure, high‐temperature superconductor nanowires, including for the first time, nanowires of the technologically important quinternary superconductor Bi2Sr2CaCu2O8+x (B2212) is demonstrated. The results of this work may provide an opportunity to investigate the physics and chemistry of highly anisotropic superconductor nanowires and enable their incorporation into nanoelectronics and energy generation systems. [ABSTRACT FROM AUTHOR]

Multicomponent flux systems based on both Li2WO4-B2O3-Li2O-CuO-Cr2O3 and Bi2O3-MoO3-B2O3-Na2O-CuO-Cr2O3 were studied in order to grow Cu2CrBO5 crystals. The conditions for Cu2CrBO5 crystallization were investigated by varyingthe component ratios, and the peculiarities of their interaction were characterized by studying the formation sequence of high-temperature crystallizing phases. Special attention was paid to the problem of Cr2O3 solubility. Phase boundaries between CuCrO2, Cu2CrO4, and Cu2CrBO5 were considered. The crystal structure of the obtained samples was studied viasingle crystal and powder X-ray diffraction. The chemical composition of the grown crystals was examined using the EDX technique. Anactual ratio of Cu:Cr = 1.89:1.11 was found for Cu2CrBO5 grown from the lithium-tungstate system, which showed a small deviation from 2:1, implying the presence of a part of bivalent Cr2+ in the samples. Anomalies in the thermal dependence of magnetization were analyzed and compared with the previously obtained data for Cu2CrBO5. The anomaly at TC ≈ 42 K and the antiferromagnetic phase transition at TN ≈ 119 K were considered. Polarized Raman spectra of Cu2CrBO5 were obtained for the first time, and a comparative analysis of the obtained data with other monoclinic and orthorhombic ludwigites is presented. Along with the polarized room temperature spectra, the thermal evolution of Raman modes near the antiferromagnetic phase transition temperature TN ≈ 119 K is provided. The influence of the magnetic phase transition on the Raman spectra of Cu2CrBO5 is discussed. [ABSTRACT FROM AUTHOR]

The flux growth of InVO4 bulk single crystals has been explored for the first time. The reported eutectic composition at a ratio of V2O5:InVO4 = 1:1 could not be used as a self-flux since no sign of melting was observed up to 1100 °C. Crystals of InVO4 of typical size 0.5 × 1 × 7 mm3 were obtained using copper pyrovanadate (Cu2V2O7) as a flux, using Pt crucibles. X-ray powder diffraction confirmed the orthorhombic Cmcm structure. Rests of the flux material were observed on the sample surface, with occasional traces of Pt indicating some level of reaction with the crucible. X-ray absorption spectroscopy showed that oxidation states of indium and vanadium ions are +3 and +5, respectively. The size and high quality of the obtained InVO4 crystals makes them excellent candidates for further study of their physical properties. [ABSTRACT FROM AUTHOR]

As devices become ever smaller and more efficient, the crystallochemically controlled synthesis of high‐performance materials that comprise their core has attracted enormous attention. Integration of complex functional materials into the next generation of electronic devices will require exquisite control of anisotropic form, either as nanotubes, nanotapes, or nanowires, yet the easy preparation of abundant quantities of them remains stubbornly challenging. Herein, a template‐free, flux‐mediated growth of vast quantities of three compositions of phase‐pure, high‐temperature superconductor nanowires, including for the first time, nanowires of the technologically important quinternary superconductor Bi2Sr2CaCu2O8+x (B2212) is demonstrated. The results of this work may provide an opportunity to investigate the physics and chemistry of highly anisotropic superconductor nanowires and enable their incorporation into nanoelectronics and energy generation systems.

TmMgB5O10 spontaneous crystals were synthesized via the flux-growth technique from a K2Mo3O10-based solvent. The crystal structure of the compound was solved and refined within the space group P21/n. The first principles calculations of the electronic structure reveal that TmMg-pentaborate with an ideal not defected crystal structure is an insulator with an indirect energy band gap of approximately 6.37 eV. Differential scanning calorimetry measurements and powder X-ray diffraction studies of heat-treated solids show that TmMgB5O10 is an incongruent melting compound. A characteristic band of the Tm3+ cation corresponding to the 3H6 → 1D2 transition is observed in the photoluminescence excitation spectra of TmMg-borate. The as-obtained crystals exhibit intense blue emission with the emission peaks centered at 455, 479, 667, and 753 nm. The most intensive band corresponds to the 1D2 → 3F4 transition. TmMgB5O10 solids demonstrate the thermal stability of photoluminescence. [ABSTRACT FROM AUTHOR]

High-quality single crystals of Bi 2 WO 6 are grown using a flux method. With different flux growth recipes, we aim to control the crystallization temperature to be lower and higher than the ferroelectric transition temperature, resulting in mono-domain and multi-domain Bi 2 WO 6 crystals, respectively. Abundant ferroelastic orthorhombic twin domains are observed in the multi-domain crystals under an optical microscope. PFM studies unveil the 90 ∘ polarization change across those ferroelastic domain walls, as well as the absence of 180 ∘ ferroelectric domains in the as-grown multi-domain crystals, indicating a high energy cost of 180 ∘ ferroelectric domains. Moreover, a 45 ∘ tilt of the 90 ∘ ferroelectric domain walls is discovered, and this tilt creates a new type of charged 90 ∘ ferroelectric walls, which have not been observed in other bulk ferroelectrics. [ABSTRACT FROM AUTHOR]

Single crystals of five (Al,Ge)-mullites incorporating Pb, and four of which also incorporating foreign cations (Fe,Cr,Nd,Sm) were grown by flux techniques in a PbO-MoO3 flux. They were characterized by scanning electron microscopy, electron microprobe analyses, single-crystal X-ray diffraction. In addition, the refractive indices of mullite containing Nd were determined by spindle-stage optical investigations. Careful inspection of the single-crystal X-ray diffraction data revealed that weak superstructure reflections observed in all doped crystals violating the reflection conditions can be attributed to λ/2 contributions in the primary X-ray beam. Consequently, all crystal structures were refined in space group Pbam, thus avoiding a symmetry lowering to a noncentrosymmetric subgroup as done in earlier work on a (Al,Ge)-mullite doped with Pb and Nd (Saalfeld & Klaska, Z. Kristallogr. 1985, 172, 129–133). The following phases with chemical compositions used in the refinements were obtained: undoped mullite (Al4.50Ge1.50O9.75; a = 7.6559(4) Å, b = 7.7763(4) Å, c = 2.9233(2) Å, V = 174.04(2) Å3); (Pb,Fe)-doped mullite (Pb0.02Fe0.68Al3.95Ge1.37O9.70; a = 7.7125(7) Å, b = 7.8527(7) Å, c = 2.9528(2) Å, V = 178.83(3) Å3); (Pb,Cr)-doped mullite (Pb0.01Cr0.63Al3.90Ge1.47O9.75; a = 7.6917(6) Å, b = 7.8168(6) Å, c = 2.9522(2) Å, V = 177.50(2) Å3); (Pb,Nd)-doped mullite (Pb0.06Nd0.02Al4.82Ge1.18O9.69; a = 7.6585(7) Å, b = 7.7666(7) Å, c = 2.9164(3) Å, V = 173.47(3) Å3); (Pb,Sm)-doped mullite (Pb0.06Sm0.02Al4.55Ge1.45O9.79; a = 7.6563(3) Å, b = 7.7873(3) Å, c = 2.9236(1) Å, V = 174.31(1) Å3); Pb is only incorporated into the crystal structure when a co-dopant element is present. Then it resides together with Nd or Sm in the oxygen-vacancy sites created by the formation of triclusters of AlO4 and GeO4 tetrahedra. In the case of (Pb,Fe)-doped mullite, Fe shares the same position as Al and Ge. In contrast to the (Al,Si)-mullites, Ge is located in both tetrahedral sites T and T*. The occupancies follow a substitution scheme according to Pbq(Nd,Sm)r(Cr,Fe)zAl4+2v−zGe2−2vO10−v+q+3/2r. With v = number of vacancies, such a mullite can be understood as a "stuffed mullite" derived from a related "open mullite" (no vacancies filled with large cations) of composition (Cr,Fe)zAl4+2v−zGe2−2vO10−v and then "stuffed" with qPb2+ + r(Nd3+,Sm3+) formula units where concurrently the number of available O3-vacancies is reduced by q + 3/2r units of extra oxygen. Thus, charge compensation upon incorporation of Pb2+ and (Nd,Sm)3+ is achieved by adding the amount of oxygen corresponding to the oxidation state of divalent Pb2+ and trivalent rare-earth elements. Based on this description, the maximum number of large cations which can be stuffed into the mullite structure can directly be calculated from the v-value of the related "open mullite". In contrast, the smaller cations Fe3+ and Cr3+ are directly substituting Al3+. In the stuffed mullites, Pb and (Nd,Sm) could not be distinguished and were refined with a mixed occupancy on the same site. In addition to structure analysis, refractive indices of (Pb,Nd)-mullite were determined by immersion methods using a micro-refractometer spindle stage yielding nx = 1.697(3), ny = 1.708(3), and nz = 1.710(3) and 2Vz = 122(4)°. The mean refractive index corresponds closely to the corresponding parameter calculated from the chemical composition whereas it would be significantly off if the extra cations were ignored, thus representing an independent evidence for the incorporation of Pb and Nd into the crystal structure. [ABSTRACT FROM AUTHOR]

Quantum fluctuations inherent in electronic systems positioned close to magnetic instabilities can lead to novel collective phenomena. One such material, β -Ti 6 Sn 5 , sits close to ferromagnetic (FM) instability and can be pushed to an itinerant FM-ordered state with only minute magnetic or non-magnetic doping. The binary nature of this compound, however, limits the tuning variables that can be applied to study any emergent physics, which are likely to be sensitive to the introduction of chemical disorder.Accordingly, we grew high-quality single crystals of a new quaternary compound Zr 3 V 3 GeSn 4 from a Sn-rich self flux, and determined the structure with single-crystal X-ray diffraction. Zr 3 V 3 GeSn 4 forms in an ordered derivative of the hexagonal β -Ti 6 Sn 5 structure with Zr and V atomic positions that show no indication of site interchange. Ge likewise occupies a single unique atomic position. The V site, which would be the one most likely to give rise to any magnetic character, is located at the center of a distorted octahedron of Sn, with such octahedra arranged in face-sharing chains along the crystallographic c axis, while the chains themselves are organized in a kagome geometry. Zr 3 V 3 GeSn 4 represents the second known quaternary phase within this system, suggesting that other compounds with this structure type await discovery. [ABSTRACT FROM AUTHOR]

High-quality single crystals of [Formula: see text] are grown using a flux method. With different flux growth recipes, we aim to control the crystallization temperature to be lower and higher than the ferroelectric transition temperature, resulting in mono-domain and multi-domain [Formula: see text] crystals, respectively. Abundant ferroelastic orthorhombic twin domains are observed in the multi-domain crystals under an optical microscope. PFM studies unveil the 90[Formula: see text] polarization change across those ferroelastic domain walls, as well as the absence of 180[Formula: see text] ferroelectric domains in the as-grown multi-domain crystals, indicating a high energy cost of 180[Formula: see text] ferroelectric domains. Moreover, a 45[Formula: see text] tilt of the 90[Formula: see text] ferroelectric domain walls is discovered, and this tilt creates a new type of charged 90[Formula: see text] ferroelectric walls, which have not been observed in other bulk ferroelectrics.

Single crystals of RE3Ni5Al19 series (RE = Y, Nd, Sm, Gd, Tb, Dy, Ho, and Er) are grown using the Al self‐flux method. The crystal structure is examined by both single crystal and powder X‐ray diffraction. Physical properties are studied for the first time for RE3Ni5Al19 (RE = Y, Nd, Gd, Tb, Dy, Ho, and Er) by means of magnetic susceptibility, electrical resistivity, and heat capacity measurements. Complex magnetic behaviors, with up to three transitions present for RE = Sm, Gd, Tb, and Dy, are revealed. Y3Ni5Al19 is found to be a nonmagnetic nonsuperconducting metal (above T = 1.8 K) with weak electron–phonon coupling strength. [ABSTRACT FROM AUTHOR]

Single crystals of the perovskite nickelate NdNiO3 with dimensions of up to 50 μm on edge have been successfully grown using the flux method at a temperature of 400 °C and oxygen pressure of 200 bar. The crystals were investigated by a combination of techniques, including high-resolution synchrotron X-ray single-crystal and powder diffraction and physical property measurements such as magnetic susceptibility and resistivity. Resistivity measurements revealed a metal-insulator transition (MIT) at TMIT~180 K with apparent thermal hysteresis; however, no superlattice peaks or peak splitting below TMIT, which corresponds to a structural transition from Pbnm to P21/n, was observed. The successful growth of NdNiO3 crystals at relatively low temperatures and oxygen pressure provides an alternative approach for preparing single crystals of interesting perovskites such as RNiO3 (R = Sm-Lu) and parent phases of superconducting square planar nickelates. [ABSTRACT FROM AUTHOR]

In this work, the growth of 0.9(Na 0.5 Bi 0.5)TiO 3 -0.1SrTiO 3 (BNT-10ST) single crystals with a maximum size of 5 × 4 × 4 mm3 was achieved using the flux method for the first time. The average structure is found to be pseudocubic, which could be due to the small rhombohedral distortions. The piezoelectric coefficient of BNT-10ST is dramatically improved to 160 pC/N, approximately 67 % higher than in ceramics of the same composition. Furthermore, the d 33 was further enhanced to 233 pC/N at 133 °C in connection with the transition from a nonergodic to an ergodic relaxor state. The single crystal exhibits a considerable maximum polarization of ⁓61.3 μC/cm2 and remnant polarization of ⁓53.7 μC/cm2. The electrostrain rose slightly from 0.1 % to 0.16 % on heating from 25 °C to 170 °C. The ferroelastic domains with a width of 15–20 μm were observed by PLM (25–360 °C). • High-quality BNT-10ST single crystals were obtained via a flux method. • The d 33 value of the single crystals (160 pC/N) is 67 % higher than that of the ceramics (∼96 pC/N). • A large remnant polarization of 53.7 μC/cm² was achieved. • Macro ferroelastic domains were observed from 25 °C to 360 °C. [ABSTRACT FROM AUTHOR]

Magnetization and heat capacity (C p) measurements were performed on blade-shaped single crystals of Li 2 CuO 2 , a one-dimensional spin-chain compound synthesized via the flux method. The magnetization and heat capacity measurements confirm a long-range antiferromagnetic transition at T N = 9.3 K. The magnetic susceptibility, χ with magnetic field applied parallel (χ ∥ b) and perpendicular (χ ⊥ b) to the spin chain direction (crystallographic b -axis) is reported. χ (T) measurements reveal anisotropic behavior, with χ ⊥ b > χ ∥ b in the temperature range T N < T < 350 K, with a ratio of χ ⊥ / χ ∥ = 1.15 at 300 K and with χ ⊥ b < χ ∥ b at T = 2 K, with a ratio of χ ⊥ / χ ∥ = 0.86 at 2 K. Unlike the previous studies reporting ferromagnetic components at low temperatures, we report the absence of a ferromagnetic ordering at low temperatures. • The magnetization and heat capacity of flux-grown single crystals of Li2CuO2 have been reported. • Antiferromagnetic long-range order is observed below 9 K. • Magnetic susceptibility along the spin chain and perpendicular to it is reported. • Unlike the previous studies on floating-zone growth single crystals, we observed no ferromagnetic spin canting at low temperatures below 2 K. [ABSTRACT FROM AUTHOR]

Multicomponent flux systems based on both Li2WO4-B2O3-Li2O-CuO-Cr2O3 and Bi2O3-MoO3-B2O3-Na2O-CuO-Cr2O3 were studied in order to grow Cu2CrBO5 crystals. The conditions for Cu2CrBO5 crystallization were investigated by varyingthe component ratios, and the peculiarities of their interaction were characterized by studying the formation sequence of high-temperature crystallizing phases. Special attention was paid to the problem of Cr2O3 solubility. Phase boundaries between CuCrO2, Cu2CrO4, and Cu2CrBO5 were considered. The crystal structure of the obtained samples was studied viasingle crystal and powder X-ray diffraction. The chemical composition of the grown crystals was examined using the EDX technique. Anactual ratio of Cu:Cr = 1.89:1.11 was found for Cu2CrBO5 grown from the lithium-tungstate system, which showed a small deviation from 2:1, implying the presence of a part of bivalent Cr2+ in the samples. Anomalies in the thermal dependence of magnetization were analyzed and compared with the previously obtained data for Cu2CrBO5. The anomaly at TC ≈ 42 K and the antiferromagnetic phase transition at TN ≈ 119 K were considered. Polarized Raman spectra of Cu2CrBO5 were obtained for the first time, and a comparative analysis of the obtained data with other monoclinic and orthorhombic ludwigites is presented. Along with the polarized room temperature spectra, the thermal evolution of Raman modes near the antiferromagnetic phase transition temperature TN ≈ 119 K is provided. The influence of the magnetic phase transition on the Raman spectra of Cu2CrBO5 is discussed.

The flux growth of InVO4 bulk single crystals has been explored for the first time. The reported eutectic composition at a ratio of V2O5:InVO4 = 1:1 could not be used as a self-flux since no sign of melting was observed up to 1100 °C. Crystals of InVO4 of typical size 0.5 × 1 × 7 mm3 were obtained using copper pyrovanadate (Cu2V2O7) as a flux, using Pt crucibles. X-ray powder diffraction confirmed the orthorhombic Cmcm structure. Rests of the flux material were observed on the sample surface, with occasional traces of Pt indicating some level of reaction with the crucible. X-ray absorption spectroscopy showed that oxidation states of indium and vanadium ions are +3 and +5, respectively. The size and high quality of the obtained InVO4 crystals makes them excellent candidates for further study of their physical properties.

A transparent Yb:YMgB5O10 single crystal with dimensions up to 25 × 23 × 25 mm and weight 10.337 g was grown using a high-temperature solution growth on dipped seeds technique with a K2Mo3O10 solvent. The Yb3+ concentration was calculated to be 4.7 at.% (NYb = 3.71 × 1020 atoms/cm3) with a distribution coefficient Kd of 0.59. The grown crystal was characterized by means of PXRD, TGA-DSC and ATR-FTIR techniques. The spectroscopic characteristics of the Yb:YMgB5O10 crystal were demonstrated. Absorption cross-section spectra were produced. The luminescence spectra of the Yb:YMgB5O10 crystal were measured in the spectral range of 950–1100 nm. The luminescence kinetics of the 2F5/2 energy level were investigated and the lifetime was determined. [ABSTRACT FROM AUTHOR]

In this study, we successfully grew large-sized single crystals (12 × 11 × 8 mm³) of 0.91Bi 0.5 Na 0.5 TiO 3 -0.06BaTiO 3 -0.03(K 0.5 Na 0.5)NbO 3 (BNT-6BT-3KNN) with a <100> c orientation using the flux growth method. This marks the first instance of achieving such crystals. The single crystals display double hysteresis loops, featuring a maximum polarization of ∼64.6 μC/cm2. Capitalizing on the nonergodic/ergodic boundary, the single crystals exhibit a substantial strain (S m) of 0.91% at the maximum electric field of 20 kV/cm and an exceptionally high inverse piezoelectric coefficient d 33 * of 4550 pm/V. The creation of long-range domains from needle-like nanodomains and polar-nano regions under the application of an electric field was confirmed through bright-field transmission electron microscopy and piezoresponse force microscopy analyses. The phase diagram for BNT-6BT-3KNN single crystals was constructed by analyzing the temperature dependence of dielectric, ferroelectric, and electrostrain behaviors. [Display omitted] [ABSTRACT FROM AUTHOR]

Single crystals of LaCr 3 (BO 3) 4 were synthesized through spontaneous nucleation from a K 2 Mo 3 O 10 flux melt. The crystal structure was determined using single-crystal X-ray diffraction (XRD) at temperatures of 293 K and 85 K. LaCr-borate crystallizes in the monoclinic C 2 /c space group with unit cell parameters a = 7.47980(5) Å, b = 9.55180(7) Å, c = 11.48330(8) Å, β = 104.0060(6)°, V = 796.04(1) Å3 (for C1, T = 293 K), and a = 7.47380(5) Å, b = 9.55520(7) Å, c = 11.47100(8) Å, β = 103.9330(6)°, V = 795.08(1) Å3 (for C2, T = 85 K), each with Z = 4. The temperature dependence of the unit cell parameters, including the monoclinic angle (β) and the unit cell volume (V), was investigated over the range of 85–293 K. No structural phase transitions were observed in the low-temperature region down to 85 K. Differential scanning calorimetry (DSC) measurements revealed no high-temperature phase transitions between 50 and 1350°C. Infrared (IR) spectroscopy confirmed the monoclinic structure of LaCr 3 (BO 3) 4 crystals, revealing characteristic absorption bands, including the lowest frequency mode associated with the translational vibrations of the La3+ ion. • Monoclinic crystals of LaCr 3 (BO 3) 4 (sp. gr. C 2/ c) were synthesized by spontaneous nucleation from the K 2 Mo 3 O 10 flux melt. • LaCr 3 (BO 3) 4 does not exhibit structural low-temperature and high-temperature phase transitions. • Monoclinic LaCr 3 (BO 3) 4 borate is a low-dimensional antiferromagnet with T N ≈ 14 K. [ABSTRACT FROM AUTHOR]

Quantum fluctuations inherent in electronic systems positioned close to magnetic instabilities can lead to novel collective phenomena. One such material, β-Ti6Sn5, sits close to ferromagnetic (FM) instability and can be pushed to an itinerant FM-ordered state with only minute magnetic or non-magnetic doping. The binary nature of this compound, however, limits the tuning variables that can be applied to study any emergent physics, which are likely to be sensitive to the introduction of chemical disorder.Accordingly, we grew high-quality single crystals of a new quaternary compound Zr3V3GeSn4 from a Sn-rich self flux, and determined the structure with single-crystal X-ray diffraction. Zr3V3GeSn4 forms in an ordered derivative of the hexagonal β-Ti6Sn5 structure with Zr and V atomic positions that show no indication of site interchange. Ge likewise occupies a single unique atomic position. The V site, which would be the one most likely to give rise to any magnetic character, is located at the center of a distorted octahedron of Sn, with such octahedra arranged in face-sharing chains along the crystallographic c axis, while the chains themselves are organized in a kagome geometry. Zr3V3GeSn4 represents the second known quaternary phase within this system, suggesting that other compounds with this structure type await discovery.

Single crystals of the perovskite nickelate NdNiO3 with dimensions of up to 50 μm on edge have been successfully grown using the flux method at a temperature of 400 °C and oxygen pressure of 200 bar. The crystals were investigated by a combination of techniques, including high-resolution synchrotron X-ray single-crystal and powder diffraction and physical property measurements such as magnetic susceptibility and resistivity. Resistivity measurements revealed a metal-insulator transition (MIT) at TMIT~180 K with apparent thermal hysteresis; however, no superlattice peaks or peak splitting below TMIT, which corresponds to a structural transition from Pbnm to P21/n, was observed. The successful growth of NdNiO3 crystals at relatively low temperatures and oxygen pressure provides an alternative approach for preparing single crystals of interesting perovskites such as RNiO3 (R = Sm-Lu) and parent phases of superconducting square planar nickelates.

A transparent Yb:YMgB5O10 single crystal with dimensions up to 25 × 23 × 25 mm and weight 10.337 g was grown using a high-temperature solution growth on dipped seeds technique with a K2Mo3O10 solvent. The Yb3+ concentration was calculated to be 4.7 at.% (NYb = 3.71 × 1020 atoms/cm3) with a distribution coefficient Kd of 0.59. The grown crystal was characterized by means of PXRD, TGA-DSC and ATR-FTIR techniques. The spectroscopic characteristics of the Yb:YMgB5O10 crystal were demonstrated. Absorption cross-section spectra were produced. The luminescence spectra of the Yb:YMgB5O10 crystal were measured in the spectral range of 950–1100 nm. The luminescence kinetics of the 2F5/2 energy level were investigated and the lifetime was determined.

A new cage-structured compound-HfMn 2 Zn 20 -belonging to the AB 2 C 20 ( A, B = transition or rare earth metals, and C = Al, Zn, or Cd) family of structures has been synthesized via the self-flux method. The new compound crystallizes in the space groupFd3¯mwith lattice parameter a ≈ 14.0543(2) Å ( Z = 8) and exhibits non-stoichiometry due to Mn/Zn mixing on the Mn-site and an underoccupied Hf-site. The structure refines to Hf 0.93 Mn 1.63 Zn 20.37 and follows lattice size trends when compared to other Hf M 2 Zn 20 ( M = Fe, Co, and Ni) structures. The magnetic measurements show that this compound displays a modified Curie-Weiss behavior with a transition temperature around 22 K. The magnetization shows no saturation, a small magnetic moment, and near negligible hysteresis, all signs of itinerant magnetism. The Rhodes-Wohlfarth ratio and the spin fluctuation parameters ratio both confirm the itinerant nature of the magnetism in HfMn 2 Zn 20 ., (© 2024 IOP Publishing Ltd.)

Hollandite-type crystals have unique and interesting physical and chemical properties. Here, we report the flux growth of hollandite-type single-crystalline potassium ferrotitanate (KFTO) with faceted surface features from a KCl flux. We varied the flux growth conditions, including the kind of flux, holding temperature, and solute concentration for growing faceted crystallites. KCl was found to be the best flux to grow the single-crystalline KFTO particles, while heating at or above 900°C was needed to yield the KFTO single crystals. The crystal growth was only weakly dependent on the solute concentration. Next, we characterized the grown single crystals and discussed the manner of their growth from the KCl flux. TEM images with clear electron diffraction spots indicated that the KFTO crystals grew along the direction to form microrods ~10 μm in size. DFT calculation results indicated that the surface energy of the (100) face is lower than that of the (001) face. Based on these characterization results, we proposed a possible growth mechanism of the KFTO crystals.

Ce1−xPrxOBiS2 (0. 1 ≤ x ≤ 0.9) single crystals were grown using a CsCl flux method. Their structural and physical properties were examined by X-ray diffraction, X-ray absorption, transmission electron microscopy, and electrical resistivity. All of the Ce1−xPrxOBiS2 single crystals with 0.1 ≤ x ≤ 0.9 exhibited tetragonal phase. With increasing Pr content, the a-axis and c-axis lattice parameters decreased and increased, respectively. Transmission electron microscope analysis of Ce0.1Pr0.9OBiS2 (x = 0.9) single crystal showed no stacking faults. Atomic-resolution energy dispersive X-ray spectrometry mapping revealed that Bi, Ce/Pr, O, and S occupied different crystallographic sites, while Ce and Pr randomly occupied the same sites. X-ray absorption spectra showed that an increase of the Pr ratio increased the ratio of Ce4+/Ce3+. All of the Ce1−xPrxOBiS2 crystals showed superconducting transition, with a maximum transition temperature of ~4 K at x = 0.9.

The triangular lattice compound TlYbS2 was prepared as large single crystals via a molten flux growth technique using sodium chloride. Anisotropic magnetic susceptibility measurements down to 0.4 K indicate a complete absence of long-range magnetic order. Despite this lack of long-range order, short-range antiferromagnetic interactions are evidenced through broad transitions, suggesting frustrated behavior. Variable magnetic field measurements reveal metamagnetic behavior at temperatures ≤2 K. Complex low temperature field-tunable magnetic behavior, in addition to no observable long-range order down to 0.4 K, suggest that TlYbS2 is a frustrated magnet and a possible quantum spin liquid candidate.

The flux growth method was successfully employed to synthesize millimeter-sized single crystals of the ternary barium vanadium pnictides Ba5V12As19+x (x ≈ 0.02) and Ba5V12Sb19+x (x ≈ 0.36), using molten Pb and Sb, respectively. Both compositions crystallize in space group P4̄3m and adopt a structure similar to those of the barium titanium pnictides Ba5Ti12Pn19+x (Pn = Sb, Bi), yet with a subtly different disorder, involving the pnictogen and barium atoms. Attempts to obtain an arsenide analog of Ba5Ti12Pn19+x using a Pb flux technique yielded binary arsenides. High-temperature treatment of the elements Ba, Ti, and As in Nb or Ta tubes resulted in side reactions with the crucible materials and produced two isostructural compositions Ba8Ti13−xMxAs21 (M = Nb, Ta; x ≈ 4), representing a new structure type. The latter structure displays fcc-type metal clusters comprised of statistically distributed Ti and M atoms (M = Nb, Ta) with multi-center and two-center bonding within the clusters, as suggested by our first-principle calculations.

High‐quality Fe1–xGaxBO3 single crystals (0.0 ≤ x ≤ 1.0) in the form of basal plates were synthesized by the flux technique. The exact content of Fe and Ga and homogeneity of their distribution in the crystal structure were determined by energy‐dispersive X‐ray spectroscopy. The crystal structure was refined using single‐crystal X‐ray diffraction data. The electronic and magnetic properties were studied using Mössbauer spectroscopy. It is shown that even a small content of diamagnetic gallium leads to a rearrangement of the crystal structure and essentially changes the magnetic hyperfine parameters of the crystals. [ABSTRACT FROM AUTHOR]

We have found conditions for reproducible spontaneous crystal growth of (RxLa1 –x)Al2.07(B4O10)O0.6 (R = Ce, Pr; x = 0, 0.003, 0.03, 0.5, 1) dimetaborate solid solutions. The composition and morphology of the crystals have been studied and limitations on isomorphous substitutions on the rare-earth site within the stability range of their structure type have been found out. We have studied the thermal properties of lanthanum dimetaborate. According to differential thermal analysis, X-ray diffraction, and analytical scanning electron microscopy data, this compound melts incongruently in the range 1120–1200°C, with a maximum endothermic peak at 1165°C. The decomposition products have been shown to include Al18B4O33, Al4B2O9, and LaBO3. [ABSTRACT FROM AUTHOR]

Ferroelectric single crystals of 0.64Pb(Mg 1/3 Nb 2/3)O 3 -0.36PbTiO 3 (PMN-PT), which have attracted lot of attention because of its excellent ferroelectric and piezoelectric response, has been successfully grown in the vicinity of morphotropic phase boundary, using high temperature solution method with PbO/B 2 O 3 as flux. The crystals were characterized for its dielectric, ferroelectric, piezoelectric and pyroelectric properties along with the investigation of its domain structure. A high Curie temperature (T c = 190 °C) was observed in the dielectric study. Well-saturated ferroelectric hysteresis loops with high remanent polarization, good switching and fatigue resistant nature indicated the high ferroelectric quality of the crystals. A high value of piezoelectric coefficient (d 33 ∗ = 1398 pm/V) was obtained from the butterfly loops. True-remanent hysteresis study unveiled the practically usable polarization value, which actually serves as memory component in devices and has never been reported for PMN-PT crystals. Time-dependent compensated hysteresis analysis was carried out to study the resistive-leakage nature of the grown crystals which is also a new study for this system. Weibull statistics was used to analyze the distribution of hardness number and to find the values of critical load for the flux grown PMN-PT crystals which helps to critically analyze materials suitability for device fabrication. [ABSTRACT FROM AUTHOR]

[(SnSe) 1+ δ ] m (NbSe 2) (m = 1–6, 8, and 12) highly orientated crystals 1–2 mm in size and well-defined c -planes were successfully grown using CsCl/KCl flux, including the first growth of crystals with m = 12. The stacked layers along the c axis in the obtained crystals were directly observed by transmission electron microscopy as m alternating layers of SnSe and single layers of NbSe 2. The superconducting transition temperature of the obtained [(SnSe) 1+ δ ] m (NbSe 2) crystals decreased with an increase in the number of SnSe layers per unit cell. As the superconducting anisotropy parameters increase, a significant increase is observed between m = 4 and 5. This indicates that the superconducting dimensionality becomes more two-dimensional with an increasing m. • We have successfully grown [(SnSe) 1+ δ ] m (NbSe 2) (m = 1–6, 8, and 12) highly orientated crystals. • The obtained [(SnSe) 1+ δ ] m (NbSe 2) highly orientated crystals exhibited the superconductivity. • A significant increase of the superconducting anisotropy was observed between m = 4 and 5. [ABSTRACT FROM AUTHOR]

• Fabricating non-polar m-plane ZnO thin films via a post NaCl flux treatment. • Possible to grow m-plane ZnO films on sapphire and quartz glass substrates. • Epitaxial growth of m-plane ZnO on c-sapphire despite its c-plane growth habit. • High crystallinity and similar photocatalytic activity to c-plane ZnO films. • Providing insights into the basic mechanisms of flux growth orientation control. We have developed a technique to fabricate non-polar m -plane ZnO thin films: the post NaCl flux treatment of Zn-containing precursors, such as amorphous zinc carbonate hydroxide, Zn 5 (CO 3) 2 (OH) 6. Conventionally, single-crystal m -plane sapphire or MgO (001) substrates have been utilized to fabricate m -plane ZnO thin films. In contrast, this method facilitates the growth of m -plane ZnO thin films on various substrates, such as sapphire and quartz glass, despite its c -plane growth habit. Furthermore, the m -plane ZnO thin film was demonstrated to epitaxially grow even on a c -plane sapphire substrate. Owing to the good lattice matching with the substrate, the m -plane ZnO epitaxial film had high crystallinity comparable to a c -plane ZnO epitaxial film that was created using a conventional pulsed laser deposition method, and exhibited similar photocatalytic activity to the c -plane ZnO film. This research offers valuable insights into the fundamental mechanisms of flux growth orientation control, which can be beneficial in designing ZnO-based electronic devices and photocatalysts. [ABSTRACT FROM AUTHOR]

This manuscript reports on the structural and magnetic properties of NdCuGa 3 using powder and single crystal X-ray diffraction (XRD), zero-field single crystal neutron diffraction, magnetization, and specific heat measurements. Our XRD on a single crystal specimen of NdCuGa 3 confirmed that it crystallizes in the tetragonal BaNiSi 3 -type structure. A magnetic phase transition at T N = 3.3 K is assessed using specific heat and ac magnetic susceptibility measurements. No additional anomaly below T N down to 50 mK was detected by performing specific heat measurements. Neutron single crystal diffraction data collected at T = 300 mK confirm the antiferromagnetic phase below T N = 3.3 K with the propagation vector τ → = (0.2, 0, 0). Possible magnetic structure solutions of NdCuGa 3 are discussed. • Single crystal XRD was used to solve crystal structure of NdCuGa 3 single crystals. • Single crystals neutron diffraction confirms the antiferromagnetic phase transition of NdCuGa 3 below T N = 3.3 K. • NdCuGa 3 belongs to RTX3 family. • NdCuGa 3 exhibits complex magnetic phase transitions below T N = 3.3 K. [ABSTRACT FROM AUTHOR]

A number of rare-earth alumo-silicides (R-Al-Si) have been synthesized from the corresponding elements by high-temperature reactions, carried out in excess of aluminum to serve as a flux. Under these experimental conditions, large single crystals of all R-Al-Si ternary phases were readily produced. The crystal structures these ternaries adopt were studied by means of powder and single-crystal X-ray diffraction and were classified as follows: (1) the early rare-earths (R=La, Ce, Pr, Nd, Sm, Gd) yield RAlxSi2-x, x∼1, non-stoichiometric ternary derivatives of the body-centered α-ThSi2-type; (2) the late rare-earths (R=Tb, Dy, Ho, Er, Tm) form stoichiometric R2Al3Si2 compounds that crystallize in the C-centered monoclinic Y2Al 3Si2-type; (3) the divalent Eu and Yb produce EuAl 2Si2 and YbAl2Si2 with the trigonal CaAl2Si2-type, whereas the last lanthanide element, Lu, forms LuAlSi with C-centered orthorhombic YAlGe-type. These structural trends are reviewed, and the evolution of the basic physical properties such as magnetism, heat capacity and electrical resistivity when moving across the series is described in detail. © 2005 Elsevier Inc. All rights reserved.

La2USe3S2, exact composition La2USe2.96S2.04, crystallized from a reaction between USe2 and La2S3 in a molten CsCl/KCl eutectic flux and was characterized by single crystal X-ray diffraction. La2USe3S2 crystallizes in the orthorhombic space group Pnma in the U3S5 structure type with lattice parameters a = 12.3284(3) Å, b = 8.4028(2) Å, and c = 7.3452(2) Å. In La2USe3S2 all the anion sites have mixed S and Se occupancy and, henceforth, will be simply referred to as Q sites. The compound exhibits sigmoidal sheets built from LaQ8 (Q = S, Se) bicapped trigonal prisms that edge-share down the a-axis forming rectangular-shaped channels or tunnels. These tunnels are occupied by UQ6 (Q = S, Se) octahedra that edge-share to form infinite, one-dimensional chains running down the b-axis. X-ray diffraction quality single crystals of La2USe3S2 were grown from a molten CsCl/KCl eutectic flux at 950 °C and used for structure determination using single crystal X-ray diffraction. The compound crystallizes in the orthorhombic space group Pnma in the U3S5 structure type. [ABSTRACT FROM AUTHOR]

Abstract Single crystals of six new alkali lanthanide silicates and germanates were synthesized via the flux growth method. A 2 CeSi 3 O 9 (A = Rb, Cs) and Cs 2 CeGe 3 O 9 crystallize in the Wadeite structure with space group P 6 3 / m and lattice parameters a = 7.1950(2) Å and c = 10.5109(3) Å for the Rb analogue. K 2 CeSi 3 O 9 crystallizes in a previously unobserved monoclinic distortion of the Wadeite structure with space group P 2 1 / n and lattice parameters a = 7.0801(2) Å, b = 10.458(2) Å, c = 12.238(2) Å and β = 90.07(3)°. Finally, Cs 8 Dy 2 Ge 16 O 39 and Cs 8 Dy 2 Ge 16 O 38 F 2 crystallize in two new structure types that are related to each other and to the Wadeite structure. Cs 8 Dy 2 Ge 16 O 39 crystallizes in the monoclinic space group P 2/ c with lattice parameters a = 12.4054(3) Å, b = 7.4310(2) Å, c = 24.5761(6) Å, and β = 90.8849(16)° and Cs 8 Dy 2 Ge 16 O 38 F 2 crystallizes in the orthorhombic space group Pnn 2 with lattice parameters a = 12.3489(4) Å, b = 12.4805(5) Å, and c = 7.3802(3) Å. The synthesis and structure of the six compounds are reported and the crystallochemical reasons for the formation of each structure are discussed. Graphical abstract Alkali rare earth germanates crystallizing in the Wadeite structure type and related structures. fx1 Highlights • Six new alkali rare earth silicates and germinates are grown from molten fluxes. • The compounds crystallize in the Wadeite and new, related structure types. • The crystallochemical reasons for the formation of each structure are discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we investigated the Al–Sn flux system and its growth conditions to obtain AlN single crystals. AlN single crystals of a size of 50 μm were successfully grown using an Al–Sn melt under nitrogen gas pressure. The growable region of the AlN crystals was established using a pressure‐temperature diagram. The required nitrogen gas pressure for the growth of the AlN crystals was found to decrease with increasing temperature, and AlN was grown at 0.1 MPa nitrogen pressure above 1300°C. By investigating the AlN yield with various Al concentrations, we confirmed that the Al component in the Al–Sn melt facilitated nitrogen dissolution. Finally, scanning electron microscopy analysis showed that the obtained AlN particles showed good morphology. [ABSTRACT FROM AUTHOR]

Perovskite LaFeO 3 is regarded as one of the promising photocatalysts for solar splitting of water to hydrogen and oxygen due to its suitable band edge positions, visible light absorbance, and high chemical stability. To further improve its photocatalytic performance of LaFeO 3 , the effects of solute concentration in the KCl-flux growth and partial A – and B –site substitution are investigated in this work. Controlling the solute concentration in the range of 1–20 mol% is crucial to grow phase-pure LaFeO 3 crystals with idiomorphic shape. With increasing the solute concentration, the flux-based growth route gradually changes to a solid state-based growth route because of a decrease in solubility and an increase in the crystallization core number. The La 1− x Sr x Fe 1− y Ti y O 3 ( x,y = 0,0; 0,0.15; 0.15,0; 0.1125,0.0375; 0.0375,0.1125; and 0.075,0.075) crystals were also synthesized by a KCl-flux method to explore the effect of partial Sr 2+ -to-La 3+ and/or Ti 4+ -to-Fe 2−4+ substitution on photocatalytic performance of LaFeO 3 . The Sr 2+ –Ti 4+ co-substitution is found to enhance the photocatalytic performance of LaFeO 3 as compared with the corresponding individual substitution (Sr 2+ or Ti 4+ ). The highest photocatalytic hydrogen generation rate (83.2 μmol h −1 ) was observed for Pt-photodeposited La 0.925 Sr 0.075 Fe 0.925 Ti 0.075 O 3 crystals in 5-h reaction due to the improvement of both bulk properties and photoactivity and the reduction in both grain boundaries and lattice defects stemmed from the Sr 2+ –Ti 4+ co-substitution and KCl flux growth. [ABSTRACT FROM AUTHOR]

Materials discovery and optimization has driven the rapid technological advancements that have been observed in our lifetimes. For this advancement to continue, solid-state chemists must continue to develop new materials. Where do these new materials come from? In this review, we discuss the approaches used by the zur Loye group to discover the next "First Material", a new material exhibiting a desired or not previously observed property that can be optimized for use in the technologies of tomorrow. Specifically, we discuss several crystal growth techniques that we have used with great success to synthesize new materials: the flux growth method, the hydroflux method, and the mild-hydrothermal method. [ABSTRACT FROM AUTHOR]

Ytterbium doped langbeinite K 2 Ti 1.887 Yb 0.113 (PO 4 ) 3 (KTYP) single crystals were grown using high temperature molten salt flux growth method. Inclusion-free KTYP crystals with sizes up to 3×3×3 mm 3 were attained using K 6 P 4 O 13 molten flux. The complete melting point of solute and solvent is above at 1223 K. Langbeinite phase KTYP crystals are growing in higher concentration of Yb 2 O 3 in flux solution. KTYP emits a strong cooperative blue emission centered at 488 nm owing to Yb-Yb pairs under 980 nm laser excitation. To the best of our knowledge, phosphate based langbeinite crystal found exhibit cooperative upconversion emission at ~488 nm. [ABSTRACT FROM AUTHOR]