Bis{2-[(1H-pyrrol-2-yl)methyl­imino­meth­yl]phenolato-κ2 N,O}zinc(II)

In the title compound, [Zn(C12H11N2O)2], the ZnII atom, lying on an inversion center, is coordinated by two O atoms and two N atoms from two salicylal Schiff base ligands in a distorted square-planar geometry. A three-dimensional network is formed by inter­molecular C—H⋯N hydrogen bonds and C—H⋯π contacts

Visualizing symmetry-breaking electronic orders in epitaxial Kagome magnet FeSn films

Kagome lattice hosts a plethora of quantum states arising from the interplay of topology, spin-orbit coupling, and electron correlations. Here, we report symmetry-breaking electronic orders tunable by an applied magnetic field in a model Kagome magnet FeSn consisting of alternating stacks of two-dimensional Fe3Sn Kagome and Sn2 honeycomb layers. On the Fe3Sn layer terminated FeSn thin films epitaxially grown on SrTiO3(111) substrates, we observe trimerization of the Kagome lattice using scanning tunneling microscopy/spectroscopy, breaking its six-fold rotational symmetry while preserving the transitional symmetry. Such a trimerized Kagome lattice shows an energy-dependent contrast reversal in dI/dV maps, which is significantly enhanced by bound states induced by Sn vacancy defects. This trimerized Kagome lattice also exhibits stripe modulations that are energy-dependent and tunable by an applied in-plane magnetic field, indicating symmetry-breaking nematicity from the entangled magnetic and charge degrees of freedom in antiferromagnet FeSn

Bis[(2R,6S)-4-(5-amino-3-carb­oxy-1-cyclo­propyl-6,8-difluoro-4-oxo-1,4-dihydro­quinolin-7-yl)-2,6-dimethyl­piperazin-1-ium] sulfate penta­hydrate

The title compound, C19H23F2N4O3 +·0.5SO4 2−·2.5H2O, an anti­bacterial fluoro­quinolone, crystallized as a racemic twin (major twin component = 0.633) in the chiral space group P1. The asymmetric unit contains two sparfloxacinium cations, one sulfate anion and five mol­ecules of water of solvation. The bond lengths and angles of both cations are almost identical. The quinoline ring systems in the cations are essentially planar, the mean deviations from the best plane being 0.045 (2) and 0.054 (2) Å and make π–π inter­actions with each other [centroid–centroid distances of 3.692 (4) Å and 3.744 (4) Å]. The crystal structure features inter­molecular O—H⋯O, O—H⋯S, N+—H⋯O, N+—H⋯S and N—H⋯O hydrogen bonds together with intra­molecular O—H⋯O and N—H⋯O hydrogen bonds. As a result, a three-dimensional supra­molecular structure is observed

Copper-based charge transfer multiferroics with a d9d^9 configuration

Multiferroics are materials with a coexistence of magnetic and ferroelectric order allowing the manipulation of magnetism by applications of an electric field through magnetoelectric coupling effects. Here we propose an idea to design a class of multiferroics with a $d^9$ configuration using the magnetic order in copper-oxygen layers appearing in copper oxide high-temperature superconductors by inducing ferroelectricity. Copper-based charge transfer multiferroics SnCuO2 and PbCuO2 having the inversion symmetry breaking $P4mm$ polar space group are predicted to be such materials. The active inner s electrons in Sn and Pb hybridize with O $2p$ states leading the buckling in copper-oxygen layers and thus induces ferroelectricity, which is known as the lone pair mechanism. As a result of the $d^9$ configuration, SnCuO2 and PbCuO2 are charge transfer insulators with the antiferromagnetic ground state of the moment on Cu retaining some strongly correlated physical properties of parent compounds of copper oxide high-temperature superconductors. Our work reveals the possibility of designing multiferroics based on copper oxide high-temperature superconductors.Comment: 18 pages, 5 figures, 1 tabl

Elemental topological ferroelectrics and polar metals of few-layer materials

Ferroelectricity can exist in elemental phases as a result of charge transfers between atoms occupying inequivalent Wyckoff positions. We investigate the emergence of ferroelectricity in two-dimensional elemental materials with buckled honeycomb lattices. Various multi-bilayer structures hosting ferroelectricity are designed by stacking-engineering. Ferroelectric materials candidates formed by group IV and V elements are predicted theoretically. Ultrathin Bi films show layer-stacking-dependent physical properties of ferroelectricity, topology, and metallicity. The two-bilayer Bi film with a polar stacking sequence is found to be an elemental topological ferroelectric material. Three and four bilayers Bi films with polar structures are ferroelectric-like elemental polar metals with topological nontrivial edge states. For Ge and Sn, trivial elemental polar metals are predicted. Our work reveals the possibility of design two-dimensional elemental topological ferroelectrics and polar metals by stacking-engineering.Comment: 18 pages, 6 figure

Effect of Scrophularia ningpoensis extract on diabetes in rats

Purpose: To investigate the effect of Scrophularia ningpoensis extract (SNE) on streptozotocin-induced diabetic rats.Methods: SNE was obtained by steeping the dried Scrophularia ningpoensis in water at 60 oC three times, each for 1 h, before first drying in an oven at 100 oC and then freeze-drying the last extract thus obtained. Diabetic rats were prepared by a single intraperitoneal injection of a freshly prepared solution of streptozotocin (50 mg/kg). The rats were randomly divided into 6 groups of ten rats each: negative control group, control group, reference group (glibenclamide1 mg/kgbody weight) as well as SNE groups, (50, 100 and 200 mg/kg). Blood glucose and plasma insulin levels were evaluated in order to determine antihyperglycemic effect. Oxidative stress was evaluated in liver and kidney by antioxidant markers, viz, lipid peroxidation (LPO), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPx) and catalase (CAT); blood serum levels of creatinine and urea were determined in both diabetic control and treated rats.Results: Compared with diabetic rats, oral administration of SNE at a concentration of 200 mg/kg daily for 30 days showed a significant decrease in fasting blood glucose to 120.21 ± 3.37 mg/dL (p < 0.05) and increased insulin level to 13.31 ± 0.67 uU/mL (p < 0.05). Furthermore, it significantly reduced biochemical parameters (serum creatinine, 0.86 ± 0.24 mg/dL, p < 0.05) and serum urea (41.86 ± 1.59 mg/dL, p < 0.05).Conclusion: The results suggest that SNE may effectively normalize impaired antioxidant status in streptozotocin-induced diabetes in a dose-dependent manner. SNE has a protective effect against lipid peroxidation by scavenging free radicals and is thus capable of reducing the risk of diabetic complications.Keywords: Scrophularia ningpoensis, Diabetic, Antihyperglycemic, Antioxidant Oxidative stress, Fasting blood glucos