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Two Fe(III)Mn(III) bimetallic compounds, [Tp*Fe (CN)₃][(Mn^IIIsalen)]·MeOH·MeCN (1) and [Tp*Fe (CN)₃][Mn^IIIsalphen]·MeOH·H₂O (2), were prepared by assembling the tricyanometalate building block (TEA)₄N [Tp*Fe(CN)₃] [Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate] and the respective Mn Schiff base precursors [salen = N,N′-ethylenebis(salicylideneiminate), salphen = N,N-bis(salicylidene)-1,2-phenylenediamine]. Both compounds exhibit a one-dimensional (1D) zigzag chain structure linked by cyanide bridges, forming a (−Fe–C≡N–Mn–N≡C−)_n motif. Magnetic studies show a gradual increase of χ_MT values in both complexes upon lowering temperature, indicating ferromagnetic coupling between the Fe^III and Mn^III metal centers with Curie–Weiss constants of +1.1 K in (1) and +1.0 K in (2). Ferromagnetic interactions are attributed to the significantly bent Mn–NC angles (148.52 and 152.99° for (1) and 154.9 and 151.3° for (2)). The formation of 1D chains in the presence of MeOH challenges earlier reports that linked chain formation to the absence of MeOH in the reaction medium. This finding highlights the highly sensitive nature of this reaction system to various factors, including the influence of solvents on intermolecular interactions, the coordinative properties and polarity of the solvent, the steric and electronic characteristics of the precursors, and specific reaction conditions, such as temperature, concentration, and molar ratios.

Chalcogenide perovskites exhibit optoelectronic properties that position them as potential materials in the field of photovoltaics. We report a detailed investigation into the electronic structure and chemical properties of polycrystalline BaZrS3 perovskite powder by X-ray photoelectron spectroscopy, complemented by an analysis of its long- and short-range geometric structures using X-ray diffraction and X-ray absorption spectroscopy. The results obtained for the powdered BaZrS3 are compared to similar measurements on a sputtered polycrystalline BaZrS3 thin film prepared through rapid thermal processing. While bulk characterization confirms the good quality of the powder, depth-profiling achieved by photoelectron spectroscopy utilizing Al K-alpha (1.487 keV) and Ga K-alpha (9.25 keV) radiations shows that, regardless of the fabrication method, the oxidation effects extend beyond 10 nm from the sample surface, with zirconium oxides specifically distributing deeper than the oxidized sulfur species. A hard X-ray photoelectron spectroscopy study on the powder and thin film detects signals with minimal contamination contributions and allows for the determination of the valence band maximum position with respect to the Fermi level. Based on these measurements, we establish a correlation between the experimental valence band spectra and the theoretical density of states derived from density functional theory calculations, thereby discerning the orbital constituents involved. Our analysis provides an improved understanding of the electronic structure of BaZrS3 developed through different synthesis protocols by linking it to material geometry, surface chemistry, and the nature of doping. This methodology can thus be adapted for describing electronic structures of chalcogenide perovskite semiconductors in general, a knowledge that is significant for interface engineering and, consequently, for device integration.

We report on, for the first time, a combined density functional theory and Boltzmann-semiclassical calculations of two-dimensional stanene half-passivated with X = H, F, Cl, Br and I The thermodynamical stability is examined through the comparison of the formation energy as well as the analysis of the phonon dispersion spectrum indicating a possible experimental fabrication of these stanene derivatives. Interestingly, using gen-eralized gradient approximation (GGA), the obtained results show that half-iodination and half-hydrogenation induce a half metallic ferromagnetic character and the magnetic moment on the unsaturated Sn atoms are 0.41 mu B and 0.38 mu B for SnSn-H and SnSn-I respectively, whereas half-decoration with fluorine, chlorine and bromine adsorbates, characterized with high electronegativity, gives rise to antiferromagnetic metallic systems. Except SnSn-I, the critical temperatures of the stanene derivatives are above room temperature. These results suggest that magnetism of stanene can be tuned by different passivation atoms. The transport properties, which result in a thermoelectric figure of merit (ZT), are very sensitive to the doping type however, less affected by the temperature variation. The highest ZT value of 0.99 is recorded for the SnSn-H conformer, while it decreases with the increase of the electronegativity. For the four compounds, the maximum figure of merit and seebeck coefficients are located at n-type doping, suggesting that these materials can be strong candidates among n-type materials for thermoelectric applications in high-temperature regions. Our findings demonstrate that half passivation with X-atoms is a feasible method to tune the properties of stanene for spin injection applications and thermoelectric cooling industry.

Transition metal trichalcogenides (TMTCs) offer remarkable opportunities for tuning electronic states through modifications in chemical composition, temperature, and pressure. Despite considerable interest in TMTCs, there remain significant knowledge gaps concerning the evolution of their electronic properties under compression. In this study, we employ experimental and theoretical approaches to comprehensively explore the high-pressure behavior of the electronic properties of TiS₃, a quasi-one-dimensional (Q1D) semiconductor, across various temperature ranges. Through high-pressure electrical resistance and magnetic measurements at elevated pressures, we uncover a distinctive sequence of phase transitions within TiS₃, encompassing a transformation from an insulating state at ambient pressure to the emergence of an incipient superconducting state above 70 GPa. Our findings provide compelling evidence that superconductivity at low temperatures of ∼2.9 K is a fundamental characteristic of TiS₃, shedding new light on the intriguing high-pressure electronic properties of TiS₃ and underscoring the broader implications of our discoveries for TMTCs in general.

Topological quantum materials hold great promise for future technological applications. Their unique electronic properties, such as protected surface states and exotic quasi-particles, offer opportunities for designing novel electronic and spintronics devices and allow quantum information processing. The origin of the interplay between various electronic orders in topological quantum materials, such as superconductivity and magnetism, remains unclear, particularly whether these electronic orders cooperate, compete, or simply coexist. Since the 2000s, the combination of topology and matter has sparked a tremendous surge of interest among theoreticians and experimentalists alike. Novel theoretical descriptions and predictions as well as complex experimental setups confirming or refuting these theories continuously appear in renowned journals. This review aims to provide conceptual tools to understand the fundamental concepts of this ever-growing field. Superconductivity and its historical development will serve as a second pillar alongside topological materials. While the main focus of this review is topological materials such as topological insulators and semimetals, topological superconductors will be explained phenomenologically.

2⁢𝐻−NbS2 is a classic example of an anisotropic multiband superconductor, with significant recent work focusing on the interesting responses seen when high magnetic fields are applied precisely parallel to the hexagonal niobium planes. It is often contrasted with its sister compound 2⁢𝐻−NbSe2 because they have similar onset temperatures for superconductivity, but 2⁢𝐻−NbS2 has no charge density wave whereas in 2⁢𝐻−NbSe2 the charge density wave order couples strongly to the superconductivity. Using small-angle neutron scattering, a bulk-sensitive probe, we have studied the vortex lattice and how it responds to the underlying superconducting anisotropy. This is done by controlling the orientation of the field with respect to the Nb planes. The superconducting anisotropy, Γ𝑎⁢𝑐=7.07±0.2, is found to be field independent over the range measured (0.15 to 1.25 T), and the magnetic field distribution as a function of the applied magnetic field is found to be in excellent quantitative agreement with anisotropic London theory modified with a core-size cutoff correction, providing the first complete validation of this model. We find values of 𝜆𝑎⁢𝑏=141.9±1.5 nm for the in-plane London penetration depth, and 𝜆𝑐∼1µ⁢m for the out-of-plane response. The field-independence indicates that we are primarily sampling the larger of the two gaps generating the superconductivity in this material.

The unique electronic properties of topological quantum materials, such as protected surface states and exotic quasiparticles, can provide an out-of-plane spin-polarized current needed for external field-free magnetization switching of magnets with perpendicular magnetic anisotropy. Conventional spin-orbit torque (SOT) materials provide only an in-plane spin-polarized current, and recently explored materials with lower crystal symmetries provide very low out-of-plane spin-polarized current components, which are not suitable for energy-efficient SOT applications. Here, we demonstrate a large out-of-plane damping-like SOT at room temperature using the topological Weyl semimetal candidate TaIrTe4 with a lower crystal symmetry. We performed spin-torque ferromagnetic resonance (STFMR) and second harmonic Hall measurements on devices based on TaIrTe₄/Ni₈₀Fe₂₀ heterostructures and observed a large out-of-plane damping-like SOT efficiency. The out-of-plane spin Hall conductivity is estimated to be (4.05±0.23)x10⁴ (ℏ/2e) (Ωm)^-1, which is an order of magnitude higher than the reported values in other materials.

Multifunctional nanosized metal-organic frameworks(NMOFs)have advanced rapidly over the past decade to develop drug deliverysystems (DDSs). These material systems still lack precise and selectivecellular targeting, as well as the fast release of the quantity ofdrugs that are simply adsorbed within and on the external surfaceof nanocarriers, which hinders their application in the drug delivery.Herein, we designed a biocompatible Zr-based NMOF with an engineeredcore and the hepatic tumor-targeting ligand, glycyrrhetinic acid graftedto polyethyleneimine (PEI) as the shell. The improved core-shellserves as a superior nanoplatform for efficient controlled and activedelivery of the anticancer drug doxorubicin (DOX) against hepaticcancer cells (HepG2 cells). In addition to their high loading capacityof 23%, the developed nanostructure DOX@NMOF-PEI-GA showed an acidicpH-stimulated response and extended the drug release time to 9 daysas well as enhanced the selectivity toward the tumor cells. Interestingly,the DOX-free nanostructures showed a minimal toxic effect on bothnormal human skin fibroblast (HSF) and hepatic cancer cell line (HepG2),but the DOX-loaded nanostructures exhibited a superior killing effecttoward the hepatic tumor, thus opening the way for the active drugdelivery and achieving efficient cancer therapy applications.

We report on a combined experimental and theoretical study on CrI3 single crystals by employing the polarization dependence of resonant inelastic x-ray scattering (RIXS). Our investigations reveal multiple Cr 3d orbital splitting (dd excitations) as well as magnetic dichroism (MD) in the RIXS spectra. The dd excitation energies are similar on the two sides of the ferromagnetic transition temperature, T-C similar to 61 K, although MD in RIXS is predominant at 0.4 T magnetic field below TC. This demonstrates that the ferromagnetic superexchange interaction that is responsible for the interatomic exchange field is vanishingly small compared with the local exchange field that comes from exchange and correlation interaction among the interacting Cr 3d orbitals. The recorded RIXS spectra reported here reveal clearly resolved Cr 3d intraorbital dd excitations that represent transitions between electronic levels that are heavily influenced by dynamic correlations and multiconfiguration effects. Our calculations taking into account the Cr 3d hybridization with the ligand valence states and the full multiplet structure due to intra-atomic and crystal field interactions in Oh and D3d symmetry clearly reproduced the dichroic trend in experimental RIXS spectra.

Transition metal dichalcogenides (TMDs) are an emergent class of low-dimensional materials with growing applications in the field of nanoelectronics. However, efficient methods for synthesizing large monocrystals of these systems are still lacking. Here, we describe an efficient synthetic route for a large number of TMDs that were obtained in quartz glass ampoules by sulfuric vapor transport and liquid sulfur. Unlike the sublimation technique, the metal enters the gas phase in the form of molecules, hence containing a greater amount of sulfur than the growing crystal. We have investigated the physical properties for a selection of these crystals and compared them to state-of-the-art findings reported in the literature. The acquired electronic properties features demonstrate the overall high quality of single crystals grown in this work as exemplified by CoS2, ReS2, NbS2, and TaS2. This new approach to synthesize high-quality TMD single crystals can alleviate many material quality concerns and is suitable for emerging electronic devices.