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In this study, the combination of octahedral Zn 2 SnO 4 with the carbon quantum dots (CQDs) is pioneered for the efficient detection of triethylamine. CQDs-modified Zn 2 SnO 4 materials were synthesized to perform rapid detection of trace triethylamine present in air. In the gas test, the optimal composite's response value to triethylamine is 600% higher than the value of the original Zn 2 SnO 4 to triethylamine, and the tendency of selective to triethylamine is more than ten times than other kinds of gases and possesses a short response/recovery times of 18 s/29 s. The exceptional properties of the composite are attributed to the superb electron transport capacity brought by the modification of 5 nm carbon quantum dots. The novel material will solve the issues of slow reaction time and low response of previous materials in detecting triethylamine. [ABSTRACT FROM AUTHOR]

This study used micro-analyses, (FTIR, UV-Vis) spectra, magnetic, thermogravimetric, X-ray powder diffraction (XRD) patterns, and transmittance electron microscopy (TEM) techniques to characterize three synthesized theophylline (TPH) complexes with ruthenium(III), platinum(IV), and iridium(III) metal ions. The metal ions indicated above were found to align with the TPH drug chelate as a mono-dentate ligand via the deprotonated NH group at the nitrogen atom position N7, as verified by FTIR measurements. Additionally, the complexes conductivity and magnetic susceptibility were examined. The octahedral geometry for the synthesized complexes was proposed by the current data. Except for the iridium(III) complex, which has a non-electrolytic nature due to the presence of a chlorine atom inside the chelation sphere, the molar conductivity of the complexes in DMSO solution was electrolyte in nature. Theophylline complexes with a (metal: ligand) stoichiometry of 1:2 were produced. The TPH complexes have also been tested in vitro against G(+) bacteria (Bacillus subtilis and Staphylococcus Aureus) and G(-) bacteria (Pseudomonas aeruginosa and Escherichia coli) to evaluate their antibacterial efficacy. Human breast and liver cancer cell lines were used as a test for the TPH complexes in vitro anti-cancer properties. [ABSTRACT FROM AUTHOR]

Hydrogen has a crucial role in preventing deactivation of sulfated zirconia (ZS). Hydro-isomerization of n-hexane is carried out with (ZS) doped with molybdenum mechanically mixed platinum supported by alumina. This catalyst presents an important improvement of the activity and stability compared to the non-doped one. At 443 K, doped and non-doped catalysts present, respectively, the activities 3 × 10–8 and 2 × 10–8 molL−1 g−1. By increasing temperature, while doped catalyst activity rises to 2.6 × 10–7 molL−1 g−1, the activity of the non-doped one drops to 3.4 × 10–9 molL−1 g−1. Characterization of solids by XRD shows the presence of ZrO2 tetragonal phase in all the solids. Raman spectroscopy confirms this finding. UV–Visible spectroscopy shows influence of calcination temperature on molybdenum geometry. At low temperature (673 K), specific surface area is developed (SBET = 144 m2 g−1) and the metal is in tetrahedral geometry as MoOx. Those sites enhance acidity and generate acid sites utilizing an atomic-scale spillover effect of H2 on platinum particles. [ABSTRACT FROM AUTHOR]

The current work aimed to fabricate a new cocaine sensor of octahedral palladium‐doped cobaltite composite (Oh‐Pd2+ : Co3O4‐C) using a simple hydrothermal protocol. As‐fabricated cocaine sensing approach was validated by various methods. Energy dispersive X‐ray analysis, X‐ray diffraction and scanning electron microscopy were recruited to characterize our charged modified composite. The electrode could sensitively detect cocaine, with a lengthy linear range (0.01 μM–900.0 μM) and a limit of detection (1.3 nM). The quantitative cocaine determination was achieved in the biological specimens using our modified electrode, the results of which displayed admirable outcomes. [ABSTRACT FROM AUTHOR]

We aim to study and investigate the structural, optical, topographical, and morphological properties of Nb2O5 thin films deposited under vacuum Q-switched Nd: YAG pulsed laser for the first time to the best of our knowledge. The obtained results of this study can contribute in different fields of applications including the optoelectronic and biomedical fields. The fundamental (1064 nm) and the visible second harmonic (532 nm) wavelengths were utilized for this purpose. The laser energy was fixed at 657 mJ. The number of pulses and the substrate temperatures were 200 laser shots and 450 °C, respectively. The observed Xray diffraction patterns were assigned for T-Nb2O5 that refers to the orthorhombic and HNb2O5 which is related to the monoclinic phases supported by Raman spectra analyses. Nb2O5 thin film deposited by Nd: YAG fundamental wavelength (1064 nm) showed a thicker film, a higher surface roughness and, on average, a larger particles size It also provided better matching of the lattice d-spacing with the standard d-spacing obtained by JPCDs cards 00-030-0873 and 00-009-0372. The optical properties including the band gap values for both direct and indirect transitions were estimated with the lower gap was reported for the thin film prepared at the fundamental wavelength. The photoluminescence analyses supported that the transitions of both prepared films were indirect. FE-SEM clarified the surface morphology of each prepared film. The EDX analyses provided the elemental compositions and the purity of the Nb2O5 prepared films. [ABSTRACT FROM AUTHOR]

[Display omitted] In this contribution, based on density Functional Theory, we focus on studying the structural and dynamic stability of octahedral and icosahedral beryllium nitride (Be 3 N 2) x fullerenes and their symmetry equivalent carbon molecules. The icosahedron structure of beryllium nitride and carbon-based fullerenes shows hybrid features, between a sphere and a polyhedron. Nevertheless, the cohesive energies of carbon fullerenes are slightly lower than those of beryllium nitride based on Be 3 N 2 units. Although icosahedral I h (1,1) and I h (2,2) (Be 3 N 2) 30 and (Be 3 N 2) 120 are energetically slightly less favorable than their corresponding carbon fullerenes, they showed chemically stable structures. IR & Raman spectra are also simulated using a coupled-perturbed KS/HF scheme permitting their identification. Importantly, no imaginary frequency is recorded in their vibrational spectra which confirms an inherent dynamic stability. These results provide valuable insights that can be extrapolated to other noncarbon nanostructures containing pentagonal rings or pentagonal defects. [ABSTRACT FROM AUTHOR]

Iron(II)-Schiff base complexes are a well-studied class of spin-crossover (SCO) active species due to their ability to interconvert between a paramagnetic high spin-state (HS, S = 2, 5T2) and a diamagnetic low spin-state (LS, S = 0, 1A1) by external stimuli under an appropriate ligand field. We have synthesized two mononuclear FeII complexes, viz., [Fe(L1)2](ClO4)2.CH3OH (1) and [Fe(L2)2](ClO4)2.2CH3CN (2), from two N6–coordinating tridentate Schiff bases derived from 2,6-bis[(benzylimino)methyl]pyridine. The complexes have been characterized by elemental analysis, electrospray ionization–mass spectrometry (ESI-MS), Fourier-transform infrared spectroscopy (FTIR), solution state nuclear magnetic resonance spectroscopy, 1H and 13C NMR (both theoretically and experimentally), single-crystal diffraction and magnetic susceptibility studies. The structural, spectroscopic and magnetic investigations revealed that 1 and 2 are with Fe–N6 distorted octahedral coordination geometry and remain locked in LS state throughout the measured temperature range from 5–350 K. [ABSTRACT FROM AUTHOR]

Cadmium substituted Co-Zn ferrites Co0.5Zn0.5CdxFe(2-x)O4 (x=0.0, 0.1, 0.2, 0.4, and 0.5) were fabricated by using the Co-precipitation method. The molecular composition and prepared samples of cubic spinel structureswas characterized using X-ray diffraction peak (XRD). X-ray diffraction patterns obtained the most intensive peak at (311) crystallographic planes for x=0.5. Williamson-Hall (W-H) relation was associated with XRD data to determine the crystallite sizes range from 25.356 nm to 35.632 nm and strain value brought into being 0.0024 to 0.0021. Tetrahedral and octahedral sites of hoping length were found to diminish from 3.6707Å-3.6332Å and 2.9967Å-2.9662Å respectively due to the addition of Cd ion concentration. TEM analysis reveals the presence of spherical shape nanoparticles with agglomeration for the prepared samples. It could be referenced based on the investigation of results for molecule size by two XRD and TEM strategies which demonstrate the development of nanomaterials and doping of cobalt ferrites. TEM results are well agreed with the XRD diffraction pattern in crystallite size by using Scherrer's formula. Fourier Transform Infrared Spectroscopy (FTIR) spectra analysis were carried out on synthesized ferrite samples and observed v1 and v2 strong absorption band in the range 400-4000 cm-1 be the possession to tetrahedral (A) and octahedral (B) sites. In FTIR, the increase of Cd2+ ion in Co-Zn ferrites leads to diminishing peak values towards lower wavenumbers. It is feasible to tune the magnetic characteristics of cobalt ferrite as a potential material for diverse technological applications by substituting Zn2+ and Cd2+ for cobalt magnetic ions. [ABSTRACT FROM AUTHOR]

A chelating ligand of thioether with ONS donor Schiff base HL [(E)-2-(((2-(benzylthio)phenyl)imino)methyl)napthalen-1-ol] and its metal complexes (RuL1 and RuL2) have been synthesized. They have been characterized by UV–Vis, FTIR, 1H NMR, 13C NMR, mass spectrometry methods. The formulas of the synthesized compounds have been confirmed by elemental analysis and magnetic susceptibility measurements. The binding ability studies of the ligand (HL) and its Ru complexes (RuL1 and RuL2), with calf-thymus DNA have been explored by the absorption titration method. The binding interaction study reveals that the ligand (HL) and the complex RuL1 interact with CT-DNA through an intercalative mode of binding whereas the complex RuL2 does not show any interaction with CT-DNA due to steric effect. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zinc copper ferrite@MWCNT was prepared via a simple hydrothermal method. • Structural and morphological analysis of composite using XRD, FESEM, and HRTEM. • It showed a high specific capacity of 646 mAh g–1 after 800 cycles at 500 mA g−1. • Composite material reveals good rate capability and outstanding cyclic stability. In this study, a novel nanocomposite material comprising pure Fe 3 O 4 (FO), doped Zn 0.5 Cu 0.5 Fe 2 O 4 -3 (ZCFO-3), and Zn 0.5 Cu 0.5 Fe 2 O 4 -3@ Multi-walled carbon nanotube (ZCFO-3@MWCNT) nanocomposite material is carefully prepared using a simple one-step hydrothermal process. Comprehensive surface and morphological analysis are conducted using X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), and High-resolution transmission electron microscopy (HRTEM), while compositional studies are investigated through Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The electrochemical performance is fully analyzed through Cyclic voltammetry (CV), Electrochemical impedance spectroscopy (EIS), rate capability tests, discharge/charge capacity, and cyclic stability evaluations. Among these three nanomaterials, ZCFO-3@MWCNT nanocomposite at 100 mA g−1 current density reveals the best performance, with a discharge capacity of 1974 mAh g–1, ZCFO-3 and FO reveal 1340 mAh g–1 and 1317 mAh g–1 respectively. After 800 cycles at 500 mA g−1 current density, ZCFO-3@MWCNT stays strong with a discharge capacity of 646 mAh g–1, while ZCFO-3 manages only 362 mAh g–1 and FO only 111 mAh g–1. After 1200 cycles at 500 mA g−1, the nanocomposite still delivers 518 mAh g–1. This study suggests that ZCFO-3@MWCNT could be a promising anode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

A series of transition metal (II) complexes with general formula [M(L1−4)2(H2O)2] (where M = Co(II), Ni(II), Cu(II) and Zn(II)) was synthesized by the reaction of metal(II) acetates with hydrazones [HL1–HL4] obtained from condensation of tetralone with hydrazide derivatives. The characterization of synthesized compounds (1–20) was done by using elemental analysis, different spectral studies (UV–Vis, 1H NMR, 13C NMR, FT-IR, mass, ESR and fluorescence), magnetic susceptibility, molar conductance measurement and thermal (DTA, TGA and DTG) analysis. The characterization results suggested the bidentate nature of the hydrazones, which chelate with the metal ion via nitrogen of (C=N) group and deprotonated carbonyl oxygen in the enolized form, resulting in stable, non-volatile octahedral complexes. The antimicrobial potential of the compounds was evaluated against four bacterial, i.e. (S. aureus, B. subtilis, P. aeruginosa and E. coli), and two fungal species, i.e. (A. niger and C. albicans), by a serial dilution method with complexes 15 and 16 as most active compounds against microbes. All the compounds were also tested for its cytotoxicity (in vitro) against three human cancer cell lines (A549, HeLa and MCF-7) and one normal cell line (L6) by the MTT assay, which focussed on an increased activity of compounds 7 and 15 towards A549, MCF-7 and HeLa cancer cell line with IC50 values ranging from 10.76 to 16.42 μg/mL, and compounds were found to be non-toxic towards L6 cell line as compared to the standard drug doxorubicin. The results demonstrated that complexation enhanced the biological activity of compounds. The synthesized compounds (1–20) were screened for antitumor activities against A549, MCF7, Hela cancer cell lines. Copper complex (7) and (15) was found to be the most active antitumor agent and less toxic against L6—Rat myoblast normal cell line than standard doxorubicin. [ABSTRACT FROM AUTHOR]

Three new water soluble ternary metal complexes, [Co(metf)(en)2]Cl2(1), [Ni(metf)(en)2]Cl2(2), and [Cu(metf)(en)2]Cl2(3), (Metf = metformin, en = ethylenediamine), were synthesized and characterized, and pharmacodynamic evaluation was reported. From the spectral analysis, octahedral geometry was proposed to all the three metal complexes. The Kinetic parameters have been determined by thermogravimetric data using Coats‐Redfern method. The stability of the complexes was obtained from their molecular orbital structures from which the quantum chemical parameters were calculated using the highest occupied molecular orbital (HOMO)‐lowest unoccupied molecular orbital (LUMO) energies. The DNA binding studies of these complexes were explored by absorption, emission, and viscosity. Groove mode of surface binding of these complexes with DNA was explained by viscosity studies. Nuclease activity exhibited by these complexes on pUC19 DNA was experimented by agarose gel electrophoresis. Discovery Studio 2.1 software was used for docking studies of these complexes into B‐DNA sequence, 5′(D*AP*CP*CP*GP*AP*CP*GP*TP*CP*GP*GP*T)‐3′ retrieved from protein data bank (PDB ID: 423D). The maximum score is seen for complex 1. The antihyperglycemic activity of these complexes was studied in streptozotocin (STZ)‐diabetic rats. The substantial increase in the antihyperglycemic activity of the complexes is seen when compared with pure drug. The maximum antihyperglycemic activity is recorded for complex 1. [ABSTRACT FROM AUTHOR]

• Pt co-catalyst enhanced the Lewis acid transformation over tungsten oxide. • Lower interaction between tungsten oxide and support lead to higher hydrogen uptake. • Crystalline tungsten oxide is the preferential sites for Lewis acid transformation. • Isolated tetrahedral tungsten oxide is stable under hydrogen. The transformation of Lewis acid sites to new Bronsted acid sites under hydrogen at 40 °C and atmospheric pressure on WO 3 /SiO 2 and WO 3 /Al 2 O 3 catalysts with various tungsten oxide loading (1, 5, 9, and 12 wt%) was investigated by the in situ DRIFTS of adsorbed NH 3. The degree of Lewis acid transformation on WO 3 /SiO 2 was higher than on WO 3 /Al 2 O 3 because the weaker interaction between WO 3 and SiO 2 showed higher hydrogen accessibility as revealed by the H 2 -TPR and H 2 -TPD results. Moreover, Pt co-catalyst with supported tungsten oxide catalyst could enhance hydrogen uptake on WO 3 catalyst, leading to higher Lewis acid transformation. However, the investigation of surface WO 3 structures were observed by XRD, FT-Raman, UV–vis, and TEM to be the key point for allowing the Lewis acid transformation. After Lewis acid transformation, isolated tetrahedral WO 3 were stable whereas octahedral polytungstate and crystalline WO 3 decreased, converting to W4+ and W5+. The decreasing of crystalline WO 3 after Lewis acid transformation was also found to be correlated well with the hydrogen uptake. Therefore, Lewis acid transformation on supported WO 3 preferentially occurred on crystalline WO 3 than on octahedral polytungstate WO 3 and isolated tetrahedral WO 3 , respectively. [ABSTRACT FROM AUTHOR]

Chemists of the late 19th century, including Alfred Werner, prepared salts containing either green or violet cations of composition [CoCl2(en)2]+ (en is ethylenediamine, C2H8N2); we now refer to these as trans‐dichloro and cis‐dichloro species. We have discovered a third salt, purple in color, containing cations of the same elemental composition and whose asymmetric unit composition is [CoCl2(en)2]2Cl2·3H2O, in which the cobalt cations are a cis:trans dichloro pair. Such a discovery would undermine Werner's argument that if only two forms can be prepared, his octahedral theory was proven. Probably because his students never examined their crystals under a microscope, they failed to observe the 'third' species, thereby ruining Werner's argument since he relied strictly on color to identify them. That was fortunate since our purple salt would have led him to abandon, or certainly delay, his momentous discovery. Our crystals consist of a 1:1 mixture of the cis and trans cations, thereby sharing the same elemental analysis and conductivity as the single salts, but not their crystal structure, inasmuch as X‐ray diffraction had not even been discovered then. Serendipitously, our discovery would have been a great boon to his theoretical acumen, while his 'two‐color' argument may have doomed him. [ABSTRACT FROM AUTHOR]

In this research paper, we delve into the influence of crystal structure, void volumes and their ionic composition along with the atomic packing factor on the radiation attenuation properties of Al-based spinel compounds. The study investigates various Al-spinel chemical compositions explores their applications in radiation shielding. Analyzing mass attenuation coefficient (MAC) of six spinel minerals across different energy regions, we observe specific trends in scattering processes with the following sequential order: MAC Pleonaste > MAC Gahnite > MAC Hercynite > MAC Galaxite > MAC Ceylonite > MAC Spinel. The results demonstrated that the MAC values were influenced by the spinel chemical composition, crystal structure, and atomic arrangement in the lattice. Furthermore, the correlation between MAC values and the tetrahedral volume (V tet), octahedral volume (V octa), and the ratio of void volumes to the unit cell volume (R) was examined. Optimal void volumes and divalent and trivalent ion compositions were determined for different spinel minerals, leading to enhanced radiation shielding efficiency. The findings offer valuable perspectives for refining and optimization of spinel materials for use in radiation applications. • Spinel group chemical composition LAC independency. • Linear relationship between lattice parameters and LAC is established. • Crystal structure modifications for improved shielding. • Role of tetrahedral and octahedral voids in optimization of radiation shielding. [ABSTRACT FROM AUTHOR]

New Mixed ligand complexes of Cu (II)then Ni (II) with L1 (1-benzyl 2,3-dialkyl -4-4'chloro Salicylaldene) pyrazole-5-one),(L2) 2-[ (2-Benzothiazolyl) -4-methoxy phenol ],(L3) 1,5-dimethyl-4-((4-methyl-1H-imidazol-2-yl)diazenyl)-2-benzyl-1,2-dihydro-3H-pyrazol-3-one and L5 (1,10,phen) have been synthesized These ion chelates complexes have been brandedwithprimarystudy,IR,1H-NMR,UV-Vis, Molar conductivities, Attractive moments, Spectral data exhibited the(L1,L2) actions as mono anionic tridentate ligand coordinating to the metal ion through(O,N,O),(N,N,O)donor atoms, imine ligand (L4) as monoanionic bidentate coordinating through(O,N)donor atoms,(L3)acts as impartial tridentate ligand coordinating to the metal ion through(N,N,O)and (1,10,phen) acts as neutral didentate ligand coordination from through (N, N). Cu(II) and Ni(II) complexes perform to have an octahedral geometry. Bio-effect studies of the ligand besides to its metal complexes alongside numerous bacteria s.aureus, Escherichia coli, klebsiella pneumonia, Aspergillus.n, Aspergillus. f, Rhizoctoniabataicola and Trichoderma, are stated. Compounds gave the high result of bustle. [ABSTRACT FROM AUTHOR]

Facile one pot synthesis of a series of seven tetraamide macrocyclic complexes of first row transition metal ions such as Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) is carried out using malonyldihydrazide and p-nitrobenzaldehyde at room temperature using template method. The characterization and structure determination of synthesized complexes was carried out using various analytical techniques such as melting point determination, IR, UV/Visible, 1H NMR, Mass spectra, magnetic susceptibility and molar conductance measurements. The results obtained indicated towards the presence of an octahedral geometry of the complexes. The synthesized complexes were screened for their antibacterial activities. [ABSTRACT FROM AUTHOR]

Solid state reaction synthesis was employed for the production of triclinic zinc molybdate (α-ZnMoO 4) crystal. X-ray diffraction (XRD) pattern, Rietveld refinement analysis, Fourier-transform infrared (FT-IR) and Fourier-transform Raman (FT-Raman) spectroscopy confirmed that α-ZnMoO 4 exhibit a triclinic structure without evidence of any impurity phase. FT-IR spectroscopy gives information about vibrational features of Mo–O in the [MoO 4 ] clusters. The 13 active vibrational modes were observed in Raman spectra from 100 to 1000 cm−1. UV–Vis absorption spectroscopy was used for calculation of optical band gap. The band gap (E g) of 4.12 eV was observed for a direct allowed transition. The photoluminescence (PL) spectrum of α-ZnMoO 4 gives intense green emission. Microwave dielectric constant ( ε r ), temperature coefficient at the resonant frequency ( τ f ) and Q x f value were measured by Hakki-Coleman method and found to be 8.05, −121.81 p p m / o C and 48320 GHz respectively. These results suggested the applications of ZnMoO 4 in LEDs, scintillating detectors and microwave device. • Synthesis of triclinic α- ZnMoO 4 by using a solid state reaction method. • Confirmation of single phase (triclinic) formation using Rietveld refinement, XRD data, FT-IR and Raman spectra. • Investigation of optical properties using UV–Vis and photoluminescence spectroscopy. • Investigation of microwave dielectric property using Hakki-Coleman technique. [ABSTRACT FROM AUTHOR]

Abstract Octahedral CuWO 4 microstructurals were successfully obtained via a simple self-assembly solvothermal synthesis pathway for the first time. The effect of organic solvents on the morphology of copper tungstate (CuWO 4) was systematically investigated here. In addition, some other parameters, such as the reaction time, sodium salts and a possible mechanism for the formation of CuWO 4 with varied morphologies were discussed. We succeed in fabricating and characterizing an octahedral CuWO 4 and the results demonstrate that the amount of ethylene glycol (EG) and Cl− plays a critical effect on the formation of unique morphology of CuWO 4. According to our investigation, samples obtained show better photocatalytic activity toward the degradation of RhB. Our research provides some new perspective of the morphology control of CuWO 4 and is conducive to understand the relationship between the morphology of other wolframite-type microcrystals and their properties. Highlights • The 3D polyhedral CuWO 4 microstructurals are obtained via a simple self-assembly solvothermal synthesis pathway. • A reasonable formation mechanism of octahedron CuWO 4 is proposed. • The unique octahedron CuWO 4 microstructural reveals good photocatalysis properties. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract In this work, we derive expansion formulas up to arbitrary order in vibrational coordinates for the tetrahedral and octahedral vibronic Hamiltonians that involve A -type states and a -type vibrations. The root-branch approach and modularized approach enable us to derive vibronic Hamiltonians including up to two vibrational modes for 5 problems in T symmetry and 92 problems in T d symmetry within one paper. These formulas can be easily adapted to problems of T h , O , and O h symmetries. Finishing this work, we have derived general vibronic Hamiltonians for all unimodal and bimodal Jahn-Teller and pseudo-Jahn-Teller problems of cubic group systems. These bimodal formulas can be extended to cover problems that involve more than two modes. [ABSTRACT FROM AUTHOR]

Graphical abstract Octahedral-typed Fe 3 O 4 nanoparticles were used as the additive onto CI based MR suspensions, and then their magnetorheological characteristics and sedimentation stability with and without additive were investigated. Abstract To enhance suspension stability and magnetorheological (MR) effect of carbonyl iron (CI)-based MR fluids, octahedral-shaped magnetite particles were synthesized by a hydrothermal method in an autoclave and then adopted as an additive for soft-magnetic CI-based MR suspensions. Two different MR suspensions comprised of the same CI particles with a 70% weight fraction were prepared; one contained an additional 1 wt% octahedral magnetite according to the carrier fluid weight. The MR characteristics of the two MR suspensions with and without the octahedral-typed magnetite nanoparticles were tested using a rotation-typed rheometer attached with a magnetic field strength generator. The sedimentation profile of the MR suspension with and without the additive was also analyzed. The shear viscosity, shear stress, yield stress, and storage modulus from rheological tests were enhanced by the magnetic additive. [ABSTRACT FROM AUTHOR]

Abstract On the basis of research on the effect of reaction conditions on nanocrystal morphology and performance, the preparation process of octahedral catalyst is optimized, and the PtNi/C octahedral nanocrystal catalyst with well-defined structure and enhanced performance is prepared by a one-pot solvothermal method using benzoic acid as structure directing agent. In rotating disk electrode test, its mass activity and specific activity reach 4.7 and 6.6 times of the commercial Pt/C catalyst, and its stability is also higher after accelerated durability testing. In order to fill the research blank on single cell application of octahedral catalyst, membrane electrode assembly is fabricated using this PtNi/C octahedral catalyst in cathode. Compared with the control, although a lower Pt loading is employed, its cell voltage at 1000 mA cm−2 and maximum power density are increased by 27 mV and 132.8 mW cm−2, respectively, demonstrating that PtNi/C octahedral catalyst exhibits actual application potential in proton exchange membrane fuel cells. After further regulating composition and structure of alloy nanocrystals, optimizing preparation process of membrane electrode assembly and investigating the durability of single cell and stack under dynamic driving cycle conditions, Pt-based octahedral catalysts are expected to replace the conventional Pt/C catalyst. Graphical abstract Image 1 Highlights • PtNi/C octahedrals were prepared with benzoic acid as structure directing agent. • Effect of reaction conditions on octahedral morphology was investigated. • PtNi/C octahedral catalyst exhibits higher ORR performance than Pt/C (JM). • MEA fabricated using this octahedral catalyst shows enhanced cell performance. [ABSTRACT FROM AUTHOR]

Zone-centre phonon frequencies, elastic properties and sound velocities along high-symmetry directions and Debye temperature of MgTi2O4 spinel is calculated using rigid ion model. The interatomic interactions up to third nearest neighbours are also calculated. The main results of the present paper reveals that the tetrahedral bonding is stronger than the octahedral bonding. Calculated results are compared with previously available experimental and theoretical data. It is observed that the obtained results are in good agreement with the available results in literature. [ABSTRACT FROM AUTHOR]

Two new Co(II) complexes, [CoL2]X2∙2H2O, with N,N,N-tridentate triazine type ligand (L) and X = Cl− (1) or NO3− (2) are synthesized and characterized using elemental analysis, FTIR spectra, and single-crystal X-ray diffraction. Complexes 1 and 2 are crystallized in the centrosymmetric space groups P-1 and C2/c, respectively. The Co atoms are surrounded by two neutral tridentate ligands coordinated via nitrogen atoms, thus forming a distorted octahedral coordination sphere. Hirshfeld topology analyses of the molecular packing revealed that the polar Cl⋯H, O⋯H and N⋯H contacts are the most important intermolecular interactions while the nonpolar C⋯H and C⋯C (π–π stacking) contacts are weak and insignificant, respectively. DFT calculations indicated that the high-spin state is energetically more favored than the low-spin case. The Co(II) center transfers its spin density to the ligand donor atoms via the spin delocalization mechanism. Based on the atoms in molecules (AIM) results, all Co–N interactions have a predominant covalent character. The strength of the Co–N interactions decreases in the order Co–N(hydrazone) > Co–N(triazine) > Co–N(amine). The metal anti-bonding natural orbitals involved in the Co–N interactions have high and s-orbital characters. Both complexes showed good thermal stability up to 276°C and 250°C for complexes 1 and 2, respectively. [ABSTRACT FROM AUTHOR]

Additively manufacturing (AM) techniques make it possible to fabricate open-cell interconnected structures with precisely controllable micro-architectures. It has been shown that the morphology, pore size, and relative density of a porous structure determine its macro-scale homogenized mechanical properties and, thus, its biological performance as a biomaterial. In this study, we used analytical, numerical, and experimental techniques to study the elastic modulus, Poisson`s ratio, and yield stress of AM porous biomaterials made by repeating the same octahedral unit cell in all spatial directions. Analytical relationships were obtained based on both Euler-Bernoulli and Timoshenko beam theories by studying a single unit cell experiencing the loads and boundary conditions sensed in an infinite lattice structure. Both single unit cells and corresponding lattice structures were manufactured using AM and mechanically tested under compression to determine the experimental values of mechanical properties. Finite element models of both single unit cell and lattice structure were also built to estimate their mechanical properties numerically. Differences in the bulk mechanical properties of struts built in different directions were observed experimentally and were taken into account in derivation of the analytical solutions. Although the analytical and numerical results were generally in good agreement, the mechanical properties obtained by the Timoshenko beam theory were closer to numerical results. The maximum difference between analytical and numerical results for elastic modulus and Poisson's ratio was below 6%, while for yield stress it was about 13%, both occurring at the relative density of 50%. The maximum difference between the analytical and experimental values of the elastic modulus was <15% (relative density = 50%). [ABSTRACT FROM AUTHOR]

Schiff bases and their metal complexes have a number of biological activities such as antidepressant, analgesic, antimicrobial, antiviral, and antitumor. In the present studies, the 1-(( E)-(pentylimino)methyl)naphthalen-2-ol ligand is prepared by the reaction of 2-hydroxynaphthaldehyde with n-amyl amine. The ligand results in CoL, NiL and CuL complexes when reacted with the cobalt acetate, nickel acetate, and copper acetate salts respectively. The complexes along with their ligand are fully characterized by X-ray diffraction studies and biologically screened. The ligand structure reveals that it is a zwitterion species where the iminic nitrogen atom is protonated and the C-O bond shows a high double bond character. The cobalt complex has an octahedral geometry around the metal center and each nitrogen atom is in the trans position to the oxygen donor site. On the other hand, the copper complex shows a centrosymmetric square planar coordination, and in this case, the nitrogen sites are trans to each other. The complexes and the ligand are found to be more potent than the standard drugs used against some microbes in their preliminary biological studies. [ABSTRACT FROM AUTHOR]

γ-Hemolysin (γ-HL) is a hemolytic and leukotoxic bicomponent β-pore-forming toxin (β-PFT), a potent virulence factor from the Staphylococcus aureus Newman strain. In this study, we performed single-particle cryoelectron microscopy (cryo-EM) of γ-HL in a lipid environment. We observed clustering and square lattice packing of octameric HlgAB pores on the membrane bilayer and an octahedral superassembly of octameric pore complexes that we resolved at resolution of 3.5 Å. Our atomic model further demonstrated the key residues involved in hydrophobic zipping between the rim domains of adjacent octameric complexes, providing additional structural stability in PFTs post oligomerization. We also observed extra densities at the octahedral and octameric interfaces, providing insights into the plausible lipid-binding residues involved for HlgA and HlgB components. Furthermore, the hitherto elusive N-terminal region of HlgA was also resolved in our cryo-EM map, and an overall mechanism of pore formation for bicomponent β-PFTs is proposed. [Display omitted] • Cryo-EM structure of bicomponent β-PFT γ-hemolysin in liposomes • An octahedral superassembly of octameric pore complexes resolved to 3.5 Å • N-terminal region and partial β-barrel suggest wild-type pre-pore/post-pore • Identification of plausible lipid-binding residues based on observed extra densities Mishra et al. present the cryo-EM structure of the bicomponent β-pore-forming toxin (β-PFT) γ-hemolysin in a lipid membrane environment. They observe formation of an octahedral superassembly of six octamers that is further stabilized by the hydrophobic interactions between the rim domains upon detachment of γ-hemolysin from liposomes and erythrocyte membranes. [ABSTRACT FROM AUTHOR]

μ 2 -Oxido bridged dinuclear vanadium(V) Schiff base complex with the general formula [VO 2 (L)] 2 ·2CH 3 OH was synthesized and characterized. The X-ray results show the complex is dinuclear with two μ-O bridging ions, and the vanadium centers have an octahedral N 2 O 4 coordination sphere. The tridentate Schiff base ligand L coordinated to vanadium(V) center as a monoanion in the basal plane. The basal plane is completed by one of the μ-O bridges. The other μ-O bridge coordinated to vanadium(V) center as apical direction. The two oxido bridged connected the two V v centers together with the V v - O -V v angle of 101.21(6)°, the V O distances of 1.70(6) and 2.31(7) Å and the V⋯V separation of 3.113(5) Å. Finally, the complex was calcinated at 600 °C for 3 h. The FT-IR spectrum of the product shows the formation of the V 2 O 5 particles. [ABSTRACT FROM AUTHOR]

A series of six-coordinated Ni(II) complexes, with the general formula Ni(Xan)L (where Xan = = isoamyldithiocarbonato and L = 2-bromopyridine, 3-bromopyridine, 4-acetylpyridine, 3-hydroxypyridine and 2-methoxypyridine) are synthesized and characterized by the elemental analysis and various physicochemical techniques such as magnetic susceptibility and conductivity measurements, UV-visible and infrared spectral data. Based on the electronic spectra and magnetic susceptibility measurements, an octahedral geometry is proposed for all the complexes. IR spectral data show that in all these complexes substituted pyridines coordinate to the metal ion through nitrogen atoms occupying the fifth and sixth axial positions, whereas O-alkyldithiocarbonate acts as a monoanion bidentate ligand and occupies the planar positions of octahedral structures. The structure of the adduct with 3-bromopyridine is elucidated by the single crystal X-ray diffraction method. The complex crystallizes in the triclinic space group P-1 with unit cell parameters a = 6.5855(4) Å, b = 9.4984(6) Å, c = 12.4518(8) Å, α = 87.944(5)°, β = 78.843(5)°, γ = 77.794(5)°. The crystal structure of the molecule is stabilized by intermolecular C-H...S and C-H...π interactions. [ABSTRACT FROM AUTHOR]

In the present work, monoclinic bismuth vanadate (m-BiVO 4 ) nanostructures have been synthesized via simple hydrothermal method and employed for visible light driven antimicrobial and photocatalytic activity. Morphology (octahedral) and size (200–300 nm) of the m-BiVO 4 are studied using transmission electron microscopy (TEM). The crystal structure of m-BiVO 4 (monoclinic scheelite structure) is confirmed by high resolution-TEM (HRTEM) and X-ray diffraction (XRD) studies. The band gap of m-BiVO 4 was estimated to be ca. 2.42 eV through Kubelka-Munk function F(R ∞) using diffuse reflectance spectroscopy (DRS). Antimicrobial action of m-BiVO 4 is anticipated by (i) shake flask method, (ii) MTT [3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide] assay for cytotoxicity. SEM analysis has been carried on Escherichia coli ( E. coli ) before and after treatment with nanostructure materials to reveal the mechanism underlying the antimicrobial action. Antimicrobial activity is studied as a function of m-BiVO 4 concentration viz. 20, 40, 60 and 80 ppm. The bacterial growth is decreased 80% to 96%, with the increase in m-BiVO 4 concentration from 20 ppm to 80 ppm, respectively, in 2 h. Photocatalytic activity and rate kinetics of m-BiVO 4 nanostructures have been studied as a function of time on methylene blue (MB) dye degradation which is one of the waste products of textile industries and responsible for water pollution. [ABSTRACT FROM AUTHOR]

A facile sacrificial-template method combined with a post annealing treatment was developed to synthesize uniform hollow polyhedral (cubic, octahedral and dodecahedral) NiO materials. The electrochemical and lithium-ion battery performances of the shape controlled hollow polyhedral NiO materials were examined, providing us with a description of the structure-performance correlations of hollow polyhedral anodes. The lithium-ion battery performance was found to be highly dependent on the hollow polyhedral NiO morphology. The hollow dodecahedral NiO (HD-NiO) electrode exhibited excellent cycling stability, high reversible capacity and good rate capacity compared to the other two NiO samples. At a current density of 0.1 A g −1 , the hollow dodecahedral NiO electrode displayed an especially high capacity of 980 mAh g −1 after 100 cycles, which was much higher than that of the hollow cubic and octahedral NiO electrodes. Most important of all, when assembled with LiCoO 2 to construct a full lithium-ion battery (HD-NiO//LiCoO 2 ), the HD-NiO electrode exhibited a reversible capacity of 627 mAh g −1 at a current density of 0.1 A g −1 in the potential range of 1.0–3.8 V. These results clearly demonstrate that hollow polyhedral NiO has potential as an anode material in next generation lithium-ion battery systems with improved storage capacities. [ABSTRACT FROM AUTHOR]

A series of four new Schiff base transition metal complexes [Co(II), Ni(II), Cu(II) and Zn(II)] derived from N-(salicylidene)-L-alanine and N,N,N',N'-tetramethylethylene-1,2-diamine (tmen) were designed, synthesized and tested for larvicidal activity against Culex quinquefasciatus, the southern house mosquito, which is the primary vector of St. Louis encephalitis virus and West Nile virus. All the complexes were characterized by physicochemical and spectral studies such as UV-Visible, FTIR, and EPR. The X-ray crystallographic analysis of Ni(II) complex revealed that, Ni(II) cation is surrounded by nitrogen and oxygen atoms from the Schiff base ligand, the oxygen atom of a water molecule, and two nitrogen atoms from tmen. Intermolecular hydrogen bonding stabilizes the Ni(II) complex. Results indicated that all the complexes exhibited higher mosquito larvicidal activity against C. quinquefasciatus. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Morphology-controlled Pt-based catalysts were synthesized by a solvothermal method and were used as oxygen reduction reaction (ORR) catalysts in proton exchange membrane fuel cells (PEMFCs). A mild acid treatment combined with electrochemical de-alloying was used to develop Pt-skinned octahedral PtCu/C-X catalysts. PtCu/C exhibited a mass activity (MA) of 0.694 A mg Pt −1 @ 0.9 V and specific activity (SA) of 2.242 mA cm−2, respectively. After 30,000 potential cycles, the MA and SA of this catalyst were enhanced by 22% to 0.849 A mg Pt −1 and 110% to 4.697 mA cm−2, respectively. It is hypothesized that the rearrangement of surface Pt atoms in electrochemical de-alloying effectively filled the defects formed by acid treatment and enhanced the activity of the catalyst accordingly. [Display omitted] • PtCu octahedral nanoparticles were prepared by surfactant-free solvothermal method. • Electrochemical de-alloying aided in surface Pt rearrangements and skin formation. • PtCu-X catalysts exhibited high mass activity and excellent stability. • Progressive de-alloying was monitored by in-situ structure evolution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two novel supramolecular structures of Ni(II) complexes based on dithiolate-amine binary ligand systems have been reported. • The N H ··· S, N H ··· N, C H ··· S type of H-bonds bestow stable supramolecular array. • HS study shows major H ··· H, N ··· H/H ··· N and S ··· H/H ··· S type of contacts in complexes. • The MTT assay and molecular docking investigation show anti-proliferative activity of [Ni(2-ap) 2 (i-mnt)]. Dithiolate-amine binary ligand systems based two novel supramolecular structures of Ni(II) coordination compounds [Ni(2-ap) 2 (i-mnt)] (1) and [Ni 2 (i-mnt) 2 (tn) 2 ] n (2) [where i-mnt−2 : 1,1-dicyanoethylene-2,2-dithiolate, 2-ap: 2-amino pyridine, tn: 1,3-diaminopropane] have been designed, synthesized and characterized by spectroscopic techniques and X-ray crystallography. In complex 1, the N 2 S 2 coordination kernel around Ni+2 attains distorted square planar geometry (Okuniewski parameter τ/ 4 = 0.17) and its supramolecular array has a dominant influence of N H ··· N type hydrogen bonds forming significant ring geometry of graph-set-motif R 4 2 8 . The i-mnt−2 adopts a diverse coordination mode in 2 contrary to 1 resulting in a binuclear one-dimensional infinite polymeric chain structure of consecutive NiS 4 [square planar, S 4 donor set τ/ 4 = 0] and NiN 6 (octahedral) coordination kernels linked by i-mnt−2 that runs along [1 0 0] axis wherein N H ··· S, N H ··· N, C H ··· S type hydrogen bonds are believed to be crystal structure stabilizers. The Hirshfeld surface analyses (HS) at the molecular and atomic levels have been extensively studied to quantify all non-covalent interactions/contacts and the nature of ligand - metal interactions. The prominent N ··· H/H ··· N [28.1 % (1), 27.3 % (2A , NiS 4), 20 % (2B , NiN 6)] and S ··· H/H ··· S contacts [10.4 % (1), 32.8 % (2A), 29 % (2B)] presumably play vital role in crystal packing. The non-covalent interactions were further investigated by Molecular Electrostatic Potential (MEP) surface at PBE0-D3/def2-TZVP level and QTAIM optimizations (for 1). The MTT assay study using SW620 metastatic colon cancer cells shows a significant dose-dependent decline in cell proliferation with increasing concentration for 1 but for 2 , the reverse trend is followed. A molecular docking study with the APC protein has further investigated the antiproliferative activity of 1 (MTT assay). [ABSTRACT FROM AUTHOR]

We single out and study a natural class of Banach spaces – almost square Banach spaces. In an almost square space we can find, given a finite set x 1 , x 2 , … , x N in the unit sphere, a unit vector y such that ‖ x i − y ‖ is almost one. These spaces have duals that are octahedral and finite convex combinations of slices of the unit ball of an almost square space have diameter 2. We provide several examples and characterizations of almost square spaces. We prove that non-reflexive spaces which are M -ideals in their biduals are almost square. We show that every separable space containing a copy of c 0 can be renormed to be almost square. A local and a weak version of almost square spaces are also studied. [ABSTRACT FROM AUTHOR]

The structure of KBaLn 3+ (BO 3 ) 2 [Ln 3+ = Sc, Lu, Gd] was solved by Rietveld refinement of the powder X-ray diffraction data. The materials crystallize with the mineral Buetschliite [K 2 Ca(CO 3 ) 2 ] structure. The lattice parameters of KBaLn 3+ (BO 3 ) 2 [Ln 3+ = Sc, Lu, Gd] increased with increasing ionic radius of the Ln 3+ cation. In this structure, the Ln 3+ cations are octahedrally coordinated. The phase formation region is dependent on the ionic radii of the Ln 3+ cation. The optical properties of Ce 3+ , Tb 3+ and Eu 3+ and their dependence on the host lattice composition are investigated and discussed. It is noteworthy that the optical properties of these ions are independent of the Ln 3+ cation in KBaLn 3+ (BO 3 ) 2 . It is concluded that in this family of materials, the crystalline field strength and the covalence at the rare earth site is independent of the host lattice composition. [ABSTRACT FROM AUTHOR]

Transition metal complexes, Na2[M(L1L2)].H2O, where M = Cu(II), Co(II) and Ni(II) ions ; L1 and L2 are the anions of phenylalanine (Phe-) and nitrilotriacetic acid (NTA3-)respectively have been synthesized and characterized by elemental analysis, spectral (IR,UV in solidstate), magnetic susceptibility and thermogravimetric analysis (TGA). All the complexes have been suggested to show six fold octahedral geometry around the metal ion. Phenylalanine and nitrilotriacetic acid demonstrate bidentate and tetradentate behavior respectively, coordinating through their respective nitrogen atom and the oxygen atom (s) of the carboxylate group. Thermal behavior of Ni(II) complex is quite different from those of Cu(II) and Co(II) complexes which show similar type of thermal behavior. Based on their decomposition temperature, the thermal stability of the three complexes can be rated as Cu > Ni > Co. [ABSTRACT FROM AUTHOR]

Different morphologies of Cu 2 O nanostructures were successfully synthesized through a reflux method in water by changing carbohydrates as reducing agents. The effects of reducing carbohydrates with different types of concentrations, and basic conditions on the morphology and size of nanostructures were investigated. The structural and optical properties of these Cu 2 O particles were studied by using XRD, SEM and UV–visible. The characteristic results revealed that using different carbohydrates in a specific concentration in water is not only reducing agent but also a directing agent to control Cu 2 O nanostructure morphologies. A possible mechanism was proposed to explain the formation of Cu 2 O nanostructures with different morphologies. The band gaps are estimated to be 1.89–2.08 eV according to the results of the optical measurements of the Cu 2 O nanostructures. [ABSTRACT FROM AUTHOR]

Since electromagnetic pollution is becoming more and more serious, the lightweight and highly efficient microwave absorbents are urgently needed to absorb unwanted electromagnetic microwaves. In this work, single-crystal octahedral CoFe 2 O 4 nanoparticles with the diameter of about 20–25 nm were successfully incorporated into the porous carbon balls (CB) via a one-step hydrothermal method. The incorporation of the CoFe 2 O 4 nanoparticles into CB reduced the dielectric loss and increased the magnetic loss, resulting in better impedance matching. When the CoFe 2 O 4 content in CoFe 2 O 4 /CB composites was 10 wt.%, the minimum reflection loss (RL) was as low as −37.2 dB, and the frequency band of RL below −10 dB was 12.9–17.1 GHz obtained with 1.5 mm thickness. This excellent microwave absorption performance was much better than that of the pure octahedral CoFe 2 O 4 nanoparticles, CB, and CoFe 2 O 4 /CB composites with CoFe 2 O 4 content of 8.5 wt.%. Owing to the low density of 1.1–1.2 g/cm 3 and good microwave absorption, the CoFe 2 O 4 /CB composite can meet the multiple requirements of microwave absorbent. [ABSTRACT FROM AUTHOR]

We have designed and prepared a novel N 3 -donor Schiff base ligand and synthesized the corresponding two mononuclear Fe(II) complexes and compared with their Zn(II) congener. Spectroscopic, Single-crystal XRD, magnetic and DFT calculations investigations reveal that both complexes have Fe__N 6 distorted octahedral geometry and their spin states locked in the low spin state throughout the measured temperature range. [Display omitted] Investigations on the spin states of octahedral Fe(II) complexes have received special attention due to their clear discrimination in the spin states of the d-orbitals. As a means to further understand the factors that influence the spin-crossover (SCO) phenomenon in Fe(II) systems, we herein report two mononuclear Fe(II) complexes, [Fe L 2 ](ClO 4) 2 ·2CH 3 OH (1) and [Fe L 2 ](BF 4) 2 ·CH 3 CN·CH 3 OH (2), derived from a novel N 3 -donor Schiff base ligand, 2,6-bis[(3- methylbenzylimino) methyl ]pyridine (L) with varying counteranion and the diamagnetic [Zn L 2 ](BF 4) 2 congener for a comparative investigation. The complexes have been synthesized and characterized by electrospray-ionization mass spectrometry (ESI-MS), Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) spectroscopy, single-crystal X-ray diffraction (XRD) and magnetic susceptibility studies. Structural and magnetic investigations reveal that both 1 and 2 show Fe__N 6 distorted octahedral geometry and are locked in the diamagnetic LS state throughout the entire explored temperature range from 1.8 to 400 K. The LS state of [Fe L 2 ]2+ is also confirmed by comparing the experimentally found structural parameters, NMR chemical shifts and excitation energies in the visible region with density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

Complexes of nickel(II), and copper(II) were synthesized with pantadentate ligand i.e. 3,3′-thiodipropionicacid-bis(5-amino-1,3,4-thiadiazole-2-thiol) (L). The ligand was synthesized by the condensation of thiodipropionic acid and 5-amino-1,3,4-thiadiazole-2-thiol in 1:2 ratio, respectively. Synthesized ligand was characterized by elemental analysis, mass, 1 H NMR, IR, and molecular modeling. All the complexes were characterized by elemental analysis, molar conductance, magnetic moment, IR, electronic spectra, ESR, and molecular modeling. The newly synthesized complexes possessed general composition [M(L)X 2 ] where M = Ni(II), Cu(II), L = pantadentate ligand and X = Cl − , CH 3 COO − . The IR spectral data indicated that the ligand behaved as a pantadentate ligand and coordinated to the metal ion through N 2 S 3 donor atoms. The molar conductance value of Ni(II), and Cu(II) complexes in DMSO corresponded to their electrolytic behavior. On the basis of spectral study, octahedral and tetragonal geometry was assigned for Ni(II) and Cu(II) complexes, respectively. In vitro fungicidal study of ligand and its complexes was investigated against fungi Candida albicans , Candida parapsilosis , Candidia krusei , and Candida tropicalis by means of well diffusion method. [ABSTRACT FROM AUTHOR]

A series of transition metal ion complexes with new amino triazole ligands such as 4- salicylidineamino-3-(4-chlorophenoxymethyl)-5-phenylamino-1,2,4-triazole HL1, 4-salicylidenen amino-3-(4-bromo phenoxy methyl)-5-phenyl amino-1,2,4-triazole HL2 and 4-(4-bromosalicylidenen amino-3-(4-bromo phenoxy methyl)-5-phenyl amino-1,2,4-triazole HL3 have been synthesized and characterized by analytical, magnetic, electronic, infrared, ¹H NMR and ESR spectral studies. Theoctahedral structure with coordination number six has been proposed for all the metal complexes of HL1, HL2 and HL3 ligands. Antibacterial and antifungal activities of all the synthesized ligands and their metal complexes have also been studied and it is found that the metal complexes of all the ligands show moderate to high activity against tested organisms than the corresponding ligand. [ABSTRACT FROM AUTHOR]

Abstract: Two copper(II) complexes, [Cu(L)N3]n (1) and [Cu(HL)2](I3)ClO4 (2), where HL = 2-pyridylaldehydesemicarbazone, have been prepared and characterized by elemental analysis, IR and UV–Vis spectroscopy and single crystal X-ray diffraction studies. Complex 1 crystallizes in monoclinic space group P21/a, whereas, complex 2 crystallizes in triclinic space group P-1. Complex 1 is a stair-like coordination polymer with square pyramidal geometry of copper(II), whereas, complex 2 is a mononuclear cationic bis-ligand complex of octahedral copper(II). Lower coordination ability of tri-iodide or perchlorate compared to azide may be related with variations of the structures of the complexes. [Copyright &y& Elsevier]

Highlights: [•] Octa Pt-Pd nanoparticles were synthesized with silsesquioxane as capping agent. [•] Octa Pt-Pd nanoparticles display uniform morphology and favorable dispersibility. [•] Octa Pt-Pd nanoparticles have high catalytic activity for formic acid by direct process. [Copyright &y& Elsevier]

Several decades after the bis(diethyl etherate) of tungsten(IV) chloride was first mentioned in the literature, it has now at last been structurally characterized by single‐crystal X‐ray diffraction analysis, finally confirming its composition. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ultrathin titanate nanosheets, octahedral and spindle-like TiO2 are successfully prepared. [•] All the samples demonstrate a stable cycle performance. [•] Spindle-like TiO2 show a higher discharge capacity than the other two materials. [•] High proportion of {100} facets contributes to its better electrochemical performance. [ABSTRACT FROM AUTHOR]

Octahedral magnetite (FeO) nanoparticles (NPs) with dimensions ranging from 20 to 110 nm are prepared via the decomposition of iron oleate complex in the presence of cetyltrimethylammonium bromide (CTAB) and various organic solvents. It is shown that the addition of an optimal amount of CTAB prompts the growth of equi-dimensional octahedral NPs with dominant {111} facets. Moreover, it is shown that the size of the octahedral NPs can be controlled by adjusting the relative amounts of oleic acid and CTAB and choosing an appropriate high-boiling point organic solvent. The X-ray diffraction analysis results reveal that the compositions of the as-synthesized NPs are solvent-dependent and contain different amounts of iron metal, wüstite and magnetite phases. The as-synthesized NPs are oxidized to pure magnetite via an air treatment and the room-temperature magnetic properties of the resulting products are then characterized by means of a superconducting quantum interference device. The results indicate that the superparamagnetic limit for the current magnetite NPs is equal to approximately 33.3 nm at a temperature of 300 K. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Four new di- and triorganonitrato stannate complexes and related derivatives have been synthesized and characterized by infrared and Mössbauer spectroscopy. The structure of Et4N[NO3(SnClPh3)2(SnPh3NO3)] ( 1) has been determined by single-crystal X-ray diffraction analysis. In the trinuclear organostannate complex, each SnIV atom is five-coordinated and adopts a trigonal-bipyramidal trans-OXSnC3 (X=O or Cl) geometry. The overall coordination environment of the SnIV atoms is trans-octahedral for 2 and 3 or cis-trigonal-bipyramidal for 4. In the related derivatives, the NO3- anions behave as monodentate ligands. [ABSTRACT FROM AUTHOR]

The sodium complex [{Ph2P(O)NH(2,6-Me2C6H3)}Na{Ph2P(O)N(2,6-Me2C6H3)}]2 ( 2) with the ligand N-(2,6-dimethylphenyl)diphenylphosphinic amide was synthesized involving the reaction of the neutral ligand [Ph2P(O)NH(2,6-Me2C6H3)] ( 1) and sodium bis(trimethylsilyl)amide in toluene at 60 °C. The calcium complex [{Ph2P(O)NH(2,6-Me2C6H3)CaI(THF)3}I] ( 3) was obtained by the reaction between the neutral ligand 1 and anhydrous calcium diiodide in THF at ambient temperature. The solid-state structures of the complexes were established by single-crystal X-ray diffraction analysis. In the solid-state structure of 2, the sodium ion is coordinated through the chelation of oxygen atom attached to the phosphorus atom. Two different P-N and P-O bond lengths are observed, which indicates that one ligand moiety is anionic, whereas the second one is neutral. In the solid-state structure of 3, the calcium atom adopts distorted octahedral arrangement through the ligation of two phosphinic amide ligands, three THF molecules, and one iodide ion. [ABSTRACT FROM AUTHOR]