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Van der Waals ferromagnets are thrilling materials from both a fundamental and technological point of view. VI3 is an interesting example, with a complex magnetism that differentiates it from the first reported Cr based layered ferromagnets. Here, we show in an indirect way through angle resolved photoemission spectroscopy experiments, the importance of spin–orbit coupling setting the electronic properties of this material. Our light polarized photoemission measurements point to a ground state with a half-filled e ± ′ doublet, where a gap opening is triggered by spin–orbit coupling enhanced by electronic correlations. [ABSTRACT FROM AUTHOR]

The synthesis, crystal structure determination, magnetic properties and bonding interaction analysis of a novel 3d transition‐metal complex, [CrBr2(NCCH3)4](Br3), are reported. Single‐crystal X‐ray diffraction results show that [CrBr2(NCCH3)4](Br3) crystallizes in space group C2/m (No. 12) with a symmetric tribromide anion and the powder X‐ray diffraction results show the high purity of the material specimen. X‐ray photoelectron studies with a combination of magnetic measurements demonstrate that Cr adopts the 3+ oxidation state. Based on the Curie–Weiss analysis of magnetic susceptibility data, the Néel temperature is found to be around 2.2 K and the effective moment (μeff) of Cr3+ in [CrBr2(NCCH3)4](Br3) is ∼3.8 µB, which agrees with the theoretical value for Cr3+. The direct current magnetic susceptibility of the molecule shows a broad maximum at ∼2.3 K, which is consistent with the theoretical Néel temperature. The maximum temperature, however, shows no clear frequency dependence. Combined with the observed upturn in heat capacity below 2.3 K and the corresponding field dependence, it is speculated that the low‐temperature magnetic feature of a broad transition in [CrBr2(NCCH3)4](Br3) could originate from a crossover from high spin to low spin for the split d orbital level low‐lying states rather than a short‐range ordering solely; this is also supported by the molecular orbital diagram obtained from theoretical calculations. [ABSTRACT FROM AUTHOR]

The general magnetic characterisation of a series of materials in the BaNi2V2O8-BaNi2P2O8 layered honeycomb spin-1 system is reported. A change from dominantly 2-dimensional (2D) to dominantly 3-dimentional (3D) magnetic character is observed on progressing from the pure V to the pure P material. The change is continuous with composition in BaNi2(V1−xPx)2O8. But a variety of features in the temperature-dependent magnetic susceptibilities at low temperatures suggest that the magnetic system is complex. Although the Curie–Weiss temperature becomes less strongly negative on increasing the P content, an indication of increased competition between different types of magnetic coupling, the system does not appear to be approaching a quantum spin liquid state at low temperatures. [ABSTRACT FROM AUTHOR]

Highlights • Well-shaped KBa R (BO 3) 2 (R = Gd, Tb, Dy, Ho, Tm and Yb) single crystals were grown by flux method. • The anisotropic magnetic properties of KBa R (BO 3) 2 (R = Gd, Tb, Dy, Ho, Tm and Yb) were studied for the first time. • A good model with R -based triangular lattice was studied here. Abstract Crystals of the KBa R (BO 3) 2 (R = Y, Gd, Tb, Dy, Ho, Tm, Yb and Lu) rare earth borates were grown by spontaneous nucleation from a KF-B 2 O 3 flux. The crystals obtained were typically well-developed hexagonal plates about 1 mm in large dimension. The crystals were used to study the anisotropic temperature and field dependent magnetization of the materials, which are based on ideal triangular planes of magnetic rare earths. All structures were refined in space group R 3 - m by single-crystal X-ray diffraction, and in addition to the equilateral triangular rare earth plane lattice, displayed K/Ba site occupancy disorder. All magnetic compounds reveal dominantly antiferromagnetic spin interactions with no magnetic ordering above 1.8 K. With the exception of KBaGd(BO 3) 2 , magnetic anisotropy was observed for other five magnetic members of the family. The results suggest that KBa R (BO 3) 2 crystals may be of further interest for investigating the magnetic properties of rare earth ions on a triangular lattice. [ABSTRACT FROM AUTHOR]

Abstract We show that the previously unreported ternary σ phases Nb 20.4 Rh 5.7 Ge 3.9 and Nb 20.4 Rh 5.7 Si 3.9 are both superconductors with T c values of approximately 1.9 K. The superconducting transitions were characterized through temperature-dependent magnetic susceptibility, electrical resistance, and specific heat measurements. The Sommerfeld constants, γ, for Nb 20.4 Rh 5.7 Ge 3.9 and Nb 20.4 Rh 5.7 Si 3.9 are 89(1) mJ mol-f.u.−1K−2 and 86(1) mJ mol-f.u.−1K−2 (about 3.0 and 2.9 mJ mol-atom−1 K−2), respectively. The normalized specific heat jumps at T c , ΔC/γT c , are approximately 1.39 for Nb 20.4 Rh 5.7 Ge 3.9 and 1.30 for Nb 20.4 Rh 5.7 Si 3.9 , consistent with both materials being weakly coupled BCS type superconductors. Highlights • New ternary σ phase superconductors. • Superconductivity observed at ∼1.9 K for both materials. • Calculated parameters confirm BCS type superconductivity. [ABSTRACT FROM AUTHOR]

We report on the discovery and the magnetic properties of CaCo 4 (TeO 3 ) 4 Cl 2 . Single-crystal X-ray diffraction shows that this compound crystallizes on a monoclinic lattice, in the space group C 2 /c with a = 19.869(1) Å, b = 5.323(1) Å, c = 16.965(1) Å and β  = 125.091(1)°. The compound has a layered structure that additionally exhibits 1D structural motifs composed of staircase-like double chains of magnetic face- and corner-sharing [CoO 5 Cl] and [CoO 6 ] octahedra, which are linked by Ca 2+ ions and [TeO 3 ] 2 – units. Temperature-dependent magnetic measurements reveal antiferromagnetic (AFM) ordering with a Néel temperature of T N ≈ 11.5 K and an effective moment of μ eff ≈ 5.2 μ B /Co consistent with expectations for Co 2+ high spin. The Curie-Weiss temperature θ  ≈ –42.1 K indicates AFM interactions dominate between the magnetic moments. The magnetic ordering transition in the zero-field heat capacity shows a λ-type anomaly. Direction-dependent magnetic measurements on single-crystals reveal an anisotropic character of the magnetization. For H || c — corresponding to a direction within the layers and perpendicular to the double chains — the AFM transition temperature is suppressed in magnetic fields higher than ~ 7.9 T and a clearly pronounced metamagnetic phase transition is observed. [ABSTRACT FROM AUTHOR]

Fe Mössbauer spectra at different temperatures betweenand K were measured on an oriented mosaic of single crystals of. The data indicate thatis a well formed compound with narrow spectral lines, no traces of other, Fe – containing, secondary phases in the spectra and no static magnetic order. There is no discernible feature at the superconducting transition temperature in any of the hyperfine parameters. The temperature dependence of the quadrupole splitting approximately follows the empirical ‘law’. The hyperfine parameters ofare compared with those formeasured in this work, and the literature data for, and were found to be in between those for these two, ordered, 122 compounds, in agreement with the gross view ofas a structural analog ofandthat has alternating Ca- and K-layers in the structure. [ABSTRACT FROM AUTHOR]

Solution growth of single crystals from high temperature solutions often involves the separation of residual solution from the grown crystals. For many growths of intermetallic compounds, this separation has historically been achieved with the use of plugs of silica wool. Whereas this is generally efficient in a mechanical sense, it leads to a significant contamination of the decanted liquid with silica fibres. In this paper, we present a simple design for frit-disc alumina crucible sets that has made their use in the growth single crystals from high temperature solutions both simple and affordable. An alumina frit-disc allows for the clean separation of the residual liquid from the solid phase. This allows for the reuse of the decanted liquid, either for further growth of the same phase, or for subsequent growth of other, related phases. In this paper, we provide examples of the growth of isotopically substituted TbCdand icosahedral i-RCd quasicrystals, as well as the separation of (i) the closely relatedandphases and (ii)and. [ABSTRACT FROM AUTHOR]

Abstract: Single crystals of RCo2Ge2 (R=Y, La–Nd, Sm–Tm) were grown using a self-flux method and were characterized by room-temperature powder X-ray diffraction; anisotropic, temperature and field dependent magnetization; temperature and field dependent, in-plane resistivity; and specific heat measurements. In this series, the majority of the moment-bearing members order antiferromagnetically; YCo2Ge2 and LaCo2Ge2 are non-moment-bearing. Ce is trivalent in CeCo2Ge2 at high temperatures, and exhibits an enhanced electronic specific heat coefficient due to the Kondo effect at low temperatures. In addition, CeCo2Ge2 shows two low-temperature anomalies in temperature-dependent magnetization and specific heat measurements. Three members (R=Tb–Ho) have multiple phase transitions above 1.8K. Eu appears to be divalent with total angular momentum L=0. Both EuCo2Ge2 and GdCo2Ge2 manifest essentially isotropic paramagnetic properties consistent with J=S=7/2. Clear magnetic anisotropy for rare-earth members with finite L was observed, with ErCo2Ge2 and TmCo2Ge2 manifesting planar anisotropy and the rest members manifesting axial anisotropy. The experimentally estimated crystal electric field (CEF) parameters B 2 0 were calculated from the anisotropic paramagnetic θ ab and θ c values and follow a trend that agrees well with theoretical predictions. The ordering temperatures, , as well as the polycrystalline averaged paramagnetic Curie–Weiss temperature, Θ avg , for the heavy rare-earth members deviate from the de Gennes scaling, as the magnitude of both is the highest for Tb, which is sometimes seen for extremely axial systems. Except for SmCo2Ge2, metamagnetic transitions were observed at 1.8K for all members that ordered antiferromagnetically. [Copyright &y& Elsevier]

Examples of stable binary icosahedral quasicrystals are relatively rare, and at present there are no known examples featuring localized magnetic moments. These would represent an ideal model system for attaining a deeper understanding of the nature of magnetic interactions in aperiodic lattices. Here we report the discovery of a family of at least seven rare earth icosahedral binary quasicrystals, i-R-Cd (R = Gd to Tm, Y), six of which bear localized magnetic moments. Our work highlights the importance of carefully motivated searches through phase space and supports the proposal that, like icosahedral Sc12Zn88 (ref. ), binary quasicrystalline phases may well exist nearby known crystalline approximants, perhaps as peritectically forming compounds with very limited liquidus surfaces, offering very limited ranges of composition/temperature for primary solidification. [ABSTRACT FROM AUTHOR]

The results of the structural determination, magnetic characterization, and theoretical calculations of a new ruthenium‐oxo complex, Li4[Ru2OCl10]·10H2O, are presented. Single crystals were grown using solvent methods and the crystal structure was characterized by single crystal X‐ray diffraction. Li4[Ru2OCl10]·10H2O crystallizes into a low‐symmetry triclinic structure (P1) due to the much smaller Li+ cation compared to K+ cation in the tetragonal complex K4[Ru2OCl10]·H2O. The X‐ray photoelectron spectra confirm only the single valent Ru4+ in Li4[Ru2OCl10]·10H2O even though two distinct Ru sites exist in the crystal structure. Magnetic measurements reveal the diamagnetic property of Li4[Ru2OCl10]·10H2O with unpaired electrons existing on Ru4+. Furthermore, the molecular orbital analysis matches well with the observed UV and magnetic measurements. [ABSTRACT FROM AUTHOR]

We investigated the effect of Ni doping in a recently proposed quantum spin liquid (QSL) candidate Li 4 CuTeO 6. We performed a comprehensive study on the structural and magnetic properties. We find that the anti-site disorder between Li + and Cu 2 + persists until 50% Ni doping in which Ni and Cu occupy different crystallographic sites. As a result, while Cu sits in both triangular and honeycomb layers in Li 4 CuTeO 6 , Ni forms only honeycomb layer in Li 4 NiTeO 6 and Li 4 Cu 0.5 Ni 0.5 TeO 6. Our magnetic susceptibility measurements show that the Weiss temperature decreases from -145.68 K in Li 4 CuTeO 6 to -6.15 K in Li 4 NiTeO 6 as Ni doping increases, and find no hint of magnetic ordering or freezing down to 1.8 K. Our analysis implies the existence of abundant low energy excitations in these materials. • Triangular-lattice antiferromagnets hosting possible quantum spin liquids (QSL). • Unavoidable anti-site disorder between Li + and Cu 2 + ions on triangular networks. • Comprehensive study of the crystal and magnetic properties in Li 4 Cu 1 − x Ni x TeO 6. [ABSTRACT FROM AUTHOR]

The crystal growth, structure, and basic magnetic properties of TmMgGaO 4 are reported. The Tm ions are located in a planar triangular lattice consisting of distorted TmO 6 octahedra, while the Mg and Ga atoms randomly occupy intermediary bilayers of M-O triangular bipyramids. The Tm ions are positionally disordered. The material displays an antiferromagnetic Curie Weiss theta of ∼−20 −25 K, with no clear ordering visible in the magnetic susceptibility down to 1.8 K; the structure and magnetic properties suggest that ordering of the magnetic moments is frustrated by both structural disorder and the triangular magnetic motif. Single crystal magnetization measurements indicate that the magnetic properties are highly anisotropic, with large moments measured perpendicular to the triangular planes. At 2 K, a broad step-like feature is seen in the field-dependent magnetization perpendicular to the plane on applied field near 2 T. [ABSTRACT FROM AUTHOR]

We describe the doping effects on a metallic breathing pyrochlore compound, Cr 4 PtGa 17. Upon doping with Sb, i.e., Cr 4 Pt(Ga 1-x Sb x) 17 , it was found that a selective doping on one of the seven Ga sites occurs. With increasing dopant level, the ferromagnetism in the parent compound is gradually suppressed, along with a decrease in fitted Curie-Weiss temperature (from 61 (1) K to −1.8 (1) K) and effective moment (from ∼2.26 μ B /f.u. to ∼0.68 μ B /f.u.). Low-temperature heat capacity measurements confirm the absence of magnetic ordering above 0.4 K for the three most doped samples. Meanwhile, electrical resistivity measurements display a metal-semiconductor transition with increasing Sb contents, which is attributed to an increase of Fermi energy based on the calculations of electronic band structure and density of states. Moreover, we have speculated that the ferromagnetism in Cr 4 PtGa 17 is governed by itinerant electrons according to our observations. This study of Sb-doping effect on Cr 4 PtGa 17 provides deeper understanding of magnetism of this system and possibilities for future modifications. [Display omitted] • Doping effect on a metallic breathing pyrochlore compound, Cr4PtGa17, was studied. • Suppression of itinerant ferromagnetism and metallicity was observed. • Electronic structure calculations are consistent with the experimental results. • Metal-semiconductor transition was displayed in the system with Sb doping. [ABSTRACT FROM AUTHOR]

A new compound, Ba3Ga2O5Cl2, isostructural with Ba3Fe2O5Cl2, was synthesized by solid‐state reaction in air. Through single‐crystal and powder X‐ray diffraction analysis, the crystal structure was determined to be cubic with chiral space group I213 and unit‐cell parameter a = 9.928 (1) Å. The Ga3+ ions in Ba3Ga2O5Cl2 are coordinated by O atoms and form GaO4 tetrahedra. Ten neighboring GaO4 tetrahedra are further bridged through corner sharing and rotation along the body diagonal, producing the chiral structure. Magnetization measurements indicate temperature‐independent diamagnetic behavior, which is qualitatively consistent with core diamagnetism from all the constituent elements. [ABSTRACT FROM AUTHOR]

Nodal‐line semimetals (NLSs) represent a new type of topological semimetallic phase beyond Weyl and Dirac semimetals in the sense that they host closed loops or open curves of band degeneracies in the Brillouin zone. Parallel to the classification of type‐I and type‐II Weyl semimetals, there are two types of NLSs. The type‐I NLS phase has been proposed and realized in many compounds, whereas the exotic type‐II NLS phase that strongly violates Lorentz symmetry has remained elusive. First‐principles calculations show that Mg3Bi2 is a material candidate for the type‐II NLS. The band crossing is close to the Fermi level and exhibits the type‐II nature of the nodal line in this material. Spin–orbit coupling generates only a small energy gap (≈35 meV) at the nodal points and does not negate the band dispersion of Mg3Bi2 that yields the type‐II nodal line. Based on this prediction, Mg3Bi2 single crystals are synthesized and the presence of the type‐II nodal lines in the material is confirmed. The angle‐resolved photoemission spectroscopy measurements agree well with the first‐principles results below the Fermi level and thus strongly suggest Mg3Bi2 as an ideal material platform for studying the as‐yet unstudied properties of type‐II nodal‐line semimetals. The type‐II nodal‐line semimetal phase with a tilted nodal‐line band structure strongly violates Lorentz symmetry and hosts exotic electronic properties that are inaccessible in conventional nodal‐line semimetals (NLSs). In this work, a material realization of type‐II NLS is reported in Mg3Pb2 and the related physics is explored in this compound by using a combined method of density functional theory and angle‐resolved photoemission spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract PbS 2 and Pb 0.9 Ag 0.1 S 2 were prepared through the reaction of PbS with excess sulfur (and silver) at 4 GPa and 600 °C. PbS 2 crystallizes in the CuAl 2 structure type, (I 4 /mcm (#140), a = 6.1106(5) Å, c = 7.4949(6) Å, Z = 4), determined by single crystal X-ray diffraction. Its structure consists of layers of [S 2 ]2- dimers and Pb2+ in square antiprismatic coordination – a rare structure type for metal dichalcogenides. Electronic structure calculations suggest that the material should be an indirect band gap semiconductor. Consistent with the calculations, the temperature-dependent resistivity of undoped PbS 2 is that of a degenerate semiconductor, while the Ag-doped material shows metallic temperature dependent resistivity down to 2 K. The materials are both diamagnetic. For the Ag-doped material, the Seebeck coefficient is small and shows nearly linear temperature-dependent behavior from 50 to 250 K. Graphical abstract PbS 2 and Pb 0.9 Ag 0.1 S 2 were prepared by solid state reaction under high pressure. PbS 2 crystallizes in the CuAl 2 structure type, (I 4 /mcm (#140), a = 6.1106(5) Å, c = 7.4949(6) Å, Z = 4). The structure consists of layers of [S 2 ]2- dimers and Pb2+ in square antiprismatic coordination – a rare structure type for metal dichalcogenides. Undoped PbS 2 appears to be an indirect band gap semiconductor based on temperature-dependent resistivity measurements and electronic structure calculations. The Ag-doped material is a metallic conductor but is not superconducting. fx1 Highlights • PbS 2 and Pb 0.9 Ag 0.1 S 2 were prepared through solid state reaction at high pressure. • PbS 2 crystallizes in CuAl 2 structure type, rare among heavy metal dichalcogenides. • A pressure-stabilized S-S covalently bonded dimer is formed in PbS 2. • PbS 2 is an indirect-band-gap semiconductor while Pb 0.9 Ag 0.1 S 2 is metallic. [ABSTRACT FROM AUTHOR]

We report the growth, structure and characterization of BaZnGa, identifying it as the sole known ternary compound in the Ba–Zn–Ga system. Single crystals of BaZnGa can be grown out of excess Ba–Zn and adopt a tI36 structure type. There are three unique Ba sites and three M = Zn/Ga sites. Using DFT calculations we can argue that whereas one of these three M sites is probably solely occupied by Ga, the other two M sites, most likely, have mixed Zn/Ga occupancy. Temperature-dependent resistivity and magnetization measurements suggest that BaZnGa is a poor metal with no electronic or magnetic phase transitions between 1.8 and 300 K. [ABSTRACT FROM PUBLISHER]

A series of n -type oxide double perovskite semiconductors, Sr 2 In 1- x Sn x SbO 6 (0 ​≤ ​ x ​≤ ​0.3) has been synthesized; Sn4+ partially substitutes for In3+. 121Sb and 119Sn Mössbauer spectroscopy are employed to investigate the B-site cation ordering because this issue cannot be resolved by conventional diffraction techniques alone. Rigid ordering between In3+/Sn4+ and Sb5+ sites is revealed by the spectroscopic method, and hence in combination with the structural parameters extracted from the XRD structural refinements, the crystallographic structure of this series of compounds is depicted. The temperature dependent magnetic susceptibilities, band gaps, and carrier type are characterized, and the calculated band structure is presented. A series of n -type oxide double perovskite semiconductors, Sr 2 In 1- x Sn x SbO 6 (0 ​≤ ​ x ​≤ ​0.3) has been synthesized and fully characterized. Mössbauer spectroscopy are employed to investigate the B-site cation ordering because this issue cannot be resolved by conventional diffraction techniques alone. [Display omitted] • A series of n -type oxide double perovskite semiconductors, Sr 2 In 1- x Sn x SbO 6 (0 ​≤ ​ x ​≤ ​0.3) has been synthesized. • 121Sb and 119Sn Mössbauer spectroscopy are employed to investigate the B-site cation ordering. • Phases in the Sr 2 In 1- x Sn x SbO 6 (0 ​≤ ​ x ​≤ ​0.3) series all exhibit bulk diamagnetic behavior and have no magnetic transitions. • Diffuse reflectance spectra reveal that the values of both transitions show a decreasing trend with increasing Sn4+content. • The hot-point probe measurements conducted confirm Sn-dopant produces n -type carriers. [ABSTRACT FROM AUTHOR]