Investigation of optical, dielectric, and conduction mechanism in lead-free perovskite CsMnBr3.

Metallic perovskites have advantageous optical and electrical properties, making them a valuable class of semiconductors for the manufacturing of solar cells. CsMnBr3 is notable among them due to its important optical characteristics. The electrical and dielectric characteristics as a semiconductor are examined in this study. Direct transitions with a 3.29 eV bandgap and an Urbach energy of 0.96 eV are revealed by the results. Through AC conductivity, it demonstrated semiconductor characteristics at 443 K. The dielectric loss varied with frequency and peaked at high frequencies. Furthermore, as temperature rose, a relaxation peak in the electrical modulus was seen to migrate to higher frequencies. Ac conductivity is described by the double power law expression. The conduction in our compound is governed by small polaron tunneling. Based on the optical results reported in the bibliography for this sample, we realize the importance of examining the electrical characteristics to comprehend the semiconductor behavior of CsMnBr3.

Synthesis and in vitro antibacterial, antifungal, anti-proliferative activities of novel adamantane-containing thiazole compounds.

A series of (Z)-N-(adamantan-1-yl)-3,4-diarylthiazol-2(3H)-imines (5a-r) was synthesized via condensation of 1-(adamantan-1-yl)-3-arylthioureas (3a-c) with various aryl bromomethyl ketones (4a-f). The structures of the synthesized compounds were characterized by 1H NMR, 13C NMR and by X-ray crystallography. The in vitro inhibitory activities of the synthesized compounds were assessed against a panel of Gram-positive and Gram-negative bacteria, and pathogenic fungi. Compounds 5c, 5g, 5l, 5m, and 5q displayed potent broad-spectrum antibacterial activity, while compounds 5a and 5o showed activity against the tested Gram-positive bacteria. Compounds 5b, 5l and 5q displayed potent antifungal activity against Candida albicans. In addition, the synthesized compounds were evaluated for anti-proliferative activity towards five human tumor cell lines. The optimal anti-proliferative activity was attained by compounds 5e and 5k which showed potent inhibitory activity against all the tested cell lines. Molecular docking analysis reveals that compounds 5e and 5k can occupy the positions of NAD cofactor and the histone deacetylase inhibitor EX527 at the active site of SIRT1 enzyme.

A New Zn(II) Metal Hybrid Material of 5-Nitrobenzimidazolium Organic Cation (C7H6N3O2)2[ZnCl4]: Elaboration, Structure, Hirshfeld Surface, Spectroscopic, Molecular Docking Analysis, Electric and Dielectric Properties.

The slow solvent evaporation approach was used to create a single crystal of (C7H6N3O2)2[ZnCl4] at room temperature. Our compound has been investigated by single-crystal XRD which declares that the complex crystallizes in the monoclinic crystallographic system with the P21/c as a space group. The molecular arrangement of the compound can be described by slightly distorted tetrahedral ZnCl42- anionic entities and 5-nitrobenzimidazolium as cations, linked together by different non-covalent interaction types (H-bonds, Cl…Cl, π…π and C-H…π). Hirshfeld's surface study allows us to identify that the dominant contacts in the crystal building are H…Cl/Cl…H contacts (37.3%). FT-IR method was used to identify the different groups in (C7H6N3O2)2[ZnCl4]. Furthermore, impedance spectroscopy analysis in 393 ≤ T ≤ 438 K shows that the temperature dependence of DC conductivity follows Arrhenius' law. The frequency-temperature dependence of AC conductivity for the studied sample shows one region (Ea = 2.75 eV). In order to determine modes of interactions of compound with double stranded DNA, molecular docking simulations were performed at molecular level.

Crystal-structure studies of 4-phenyl-piperazin-1-ium 4-eth-oxy-benzoate monohydrate, 4-phenyl-piperazin-1-ium 4-meth-oxy-benzoate monohydrate, 4-phenyl-piperazin-1-ium 4-methyl-benzoate monohydrate and 4-phenyl-piperazin-1-ium tri-fluoro-acetate 0.12-hydrate.

In this study, four new piperazinium salts, namely, 4-phenyl-piperazin-1-ium 4-eth-oxy-benzoate monohydrate, C9H9O3·C10H15N2·H2O (I); 4-phenyl-piperazin-1-ium 4-meth-oxy-benzoate monohydrate, C10H15N2·C8H7O3·H2O (II); 4-phenyl-piperazin-1-ium 4-methyl-benzoate monohydrate, C10H15N2·C8H7O2·H2O (III); and 4-phenyl-piperazin-1-ium tri-fluoro-acetate 0.12 hydrate, C10H15N2·C2F3O2·0.12H2O (IV), have been synthesized. The single-crystal structures of these compounds reveal that all of them crystallize in the triclinic P space group and the crystal packing of (I)-(III) is built up of ribbons formed by a combination of hydrogen bonds of type N-H⋯O, O-H⋯O and other weak inter-actions of type C-H⋯O and C-H⋯π, leading to a three-dimensional network. In the crystal of (IV), the cations and the anions are connected by C-H⋯O, N-H⋯O and C-H⋯F hydrogen bonds and by C-H⋯π inter-actions, forming sheets which in turn inter-act to maintain the crystal structure by linking through the oxygen atoms of water mol-ecules and van der Waals inter-actions, giving the whole structure.

Crystal structures of six 4-(4-nitro-phenyl)-piperazin-1-ium salts.

Six piperazinium salts, namely 4-(4-nitro-phenyl)-piperazin-1-ium 4-bromo-ben-zo-ate dihydrate, C10H14N3O2 +·C7H4BrO2 -·2H2O, (I), 4-(4-nitro-phenyl)-pi-per-a-zin-1-ium 4-iodo-benzoate dihydrate, C10H14N3O2 +·C7H4IO2 -·2H2O, (II), 4-(4-nitro-phenyl)-piperazin-1-ium 4-hy-droxy-benzoate monohydrate, C10H14N3O2 +·C7H5O3 -·H2O, (III), 4-(4-nitro-phenyl)-piperazin-1-ium 4-methyl-benzoate monohydrate, C10H14N3O2 +·C8H7O2 -·H2O, (IV), 4-(4-nitro-phenyl)-piperazin-1-ium 4-meth-oxy-benzoate hemihydrate, 2C10H14N3O2 +·2C8H7O3 -·H2O, (V), and 4-(4-nitro-phenyl)-piperazin-1-ium 4-eth-oxy-benzoate, 2C10H14N3O2 +·2C9H9O3 -, (VI), have been synthesized and their crystal structures solved by single-crystal X-ray diffraction, revealing that all of them crystallize in the triclinic space group P except for (V), which crystallizes in the monoclinic space group P21/c and has a disordered nitro group. Compounds (I) and (II) are isostructural. The crystal packing of (I)-(V) is constructed from organic chains formed by a combination of hydrogen bonds of type N-H⋯O and/or O-H⋯O and other weak inter-actions of type C-H⋯O and/or C-H⋯π, forming sheets, whereas (VI) shows a cationic and anionic-based layer structure.

Structural and Electronic Effect Driven Distortions in Visible Light Absorbing Polar Materials ATa2V2O11 (A = Sr, Pb).

Complex vanadates of tantalum(V), such as ATa2V2O11 (A = Sr, Pb), are rare and underrated materials, which have potential application domains that could be substantially expanded, mitigating the existing controversy on their atomic and electronic organization. Herein, we present a thorough structural examination combining synchrotron powder X-ray diffraction-aided distortion mode analysis with computational methods to study hettotypes of SrTa2V2O11 (STVO) and PbTa2V2O11 (PTVO). Being distinct from the perovskite family due to the presence of [VO4] groups, both compounds are polar dielectric materials with certain similarities to SBT and PBT Aurivillius phases. Applying the model of anions of metallic matrices to the analysis of electron localization functions calculated on top of as-established equilibrium structures helps retrace the effects in the Sr and Pb surroundings on the respective crystal packings of STVO and PTVO.

Cobalt Minimisation in Violet Co3P2O8 Pigment.

This study considers the limitations of cobalt violet orthophosphate, Co3P2O8, in the ceramic industry due to its large amount of cobalt. MgxCo3-xP2O8 (0 ≤ x ≤ 3) solid solutions with the stable Co3P2O8 structure were synthesised via the chemical coprecipitation method. The formation of solid solutions between the isostructural Co3P2O8 and Mg3P2O8 compounds decreased the toxically large amount of cobalt in this inorganic pigment and increased the melting point to a temperature higher than 1200 °C when x ≥ 1.5. Co3P2O8 melted at 1160 °C, and compositions with x ≥ 1.5 were stable between 800 and 1200 °C. The substitution of Co(II) with Mg(II) decreased the toxicity of these materials and decreased their price; hence, the interest of these materials for the ceramic industry is greater. An interesting purple colour with a* = 31.6 and b* = -24.2 was obtained from a powdered Mg2.5Co0.5P2O8 composition fired at 1200 °C. It considerably reduced the amount of cobalt, thus improving the colour of the Co3P2O8 pigment (a* = 16.2 and b* = -20.1 at 1000 °C). Co3P2O8 is classified as an inorganic pigment (DCMA-8-11-1), and the solid solutions prepared were also inorganic pigments when unglazed. When introducing 3% of the sample (pigment) together with enamel, spreading the mixture on a ceramic support and calcining the whole in an electric oven, a colour change from violet to blue was observed due to the change in the local environment of Co(II), which could be seen in the UVV spectra of the glazed samples with the displacement of the bands towards higher wavelengths and with the appearance of a new band assigned to tetrahedral Co(II). This blue colour was also obtained with Co2SiO4, MgCoSiO4 or Co3P2O8 pigments containing a greater amount of cobalt.

Crystal structure studies of 4-ethyl-piperazin-1-ium 3,5-di-nitro-benzoate, 4-methyl-piperazin-1-ium 3,5-di-nitro-benzoate and 4-methyl-piperazin-1-ium 4-iodo-benzoate.

As part of our ongoing investigation on the chemical and biological properties of piperazinium salts, we synthesized three novel compounds: 1-ethyl-piperazinium 3,5-di-nitro-benzoate (I), 1-methyl-piperazinium 3,5-di-nitro-benzoate (II) and 1-methyl-piperazinium 4-iodo-benzoate (III). The crystal structures of these compounds are built up of organic layers formed by the strong connection between the mol-ecules by hydrogen bonds of type N-H⋯O. These layers are linked through N-H⋯O hydrogen bonds and C-H⋯O inter-actions or C-I⋯N halogen bonding, leading to the formation of a three-dimensional network.

Development of Ferromagnetic Materials Containing Co2P, Fe2P Phases from Organometallic Dendrimers Precursors.

The development of synthesis methods to access advanced materials, such as magnetic materials that combine multimetallic phosphide phases, remains a worthy research challenge. The most widely used strategies for the synthesis of magnetic transition metal phosphides (TMPs) are organometallic approaches. In this study, Fe-containing homometallic dendrimers and Fe/Co-containing heterometallic dendrimers were used to synthesize magnetic materials containing multimetallic phosphide phases. The crystalline nature of the nearly aggregated particles was indicated for both designed magnetic samples. In contrast to heterometallic samples, homometallic samples showed dendritic effects on their magnetic properties. Specifically, saturation magnetization (Ms) and coercivity (Hc) decrease as dendritic generation increases. Incorporating cobalt into the homometallic dendrimers to prepare the heterometallic dendrimers markedly increases the magnetic properties of the magnetic materials from 60 to 75 emu/g. Ferromagnetism in homometallic and heterometallic particles shows different responses to temperature changes. For example, heterometallic samples were less sensitive to temperature changes due to the presence of Co2P in contrast to the homometallic ones, which show an abrupt change in their slopes at a temperature close to 209 K, which appears to be related to the Fe2P ratios. This study presents dendrimers as a new type of precursor for the assembly of magnetic materials containing a mixture of iron- and cobalt-phosphides phases with tunable magnetism, and provides an opportunity to understand magnetism in such materials.

Structural Insights and Docking Analysis of Adamantane-Linked 1,2,4-Triazole Derivatives as Potential 11ß-HSD1 Inhibitors.

The solid-state structural analysis and docking studies of three adamantane-linked 1,2,4-triazole derivatives are presented. Crystal structure analyses revealed that compound 2 crystallizes in the triclinic P-1 space group, while compounds 1 and 3 crystallize in the same monoclinic P21/c space group. Since the only difference between them is the para substitution on the aryl group, the electronic nature of these NO2 and halogen groups seems to have no influence over the formation of the solid. However, a probable correlation with the size of the groups is not discarded due to the similar intermolecular disposition between the NO2/Cl substituted molecules. Despite the similarities, CE-B3LYP energy model calculations show that pairwise interaction energies vary between them, and therefore the total packing energy is affected. HOMO-LUMO calculated energies show that the NO2 group influences the reactivity properties characterizing the molecule as soft and with the best disposition to accept electrons. Further, in silico studies predicted that the compounds might be able to inhibit the 11ß-HSD1 enzyme, which is implicated in obesity and diabetes. Self- and cross-docking experiments revealed that a number of non-native 11ß-HSD1 inhibitors were able to accurately dock within the 11ß-HSD1 X-ray structure 4C7J. The molecular docking of the adamantane-linked 1,2,4-triazoles have similar predicted binding affinity scores compared to the 4C7J native ligand 4YQ. However, they were unable to form interactions with key active site residues. Based on these docking results, a series of potentially improved compounds were designed using computer aided drug design tools. The docking results of the new compounds showed similar predicted 11ß-HSD1 binding affinity scores as well as interactions to a known potent 11ß-HSD1 inhibitor.

Ultralight-Weight Graphene Aerogels with Extremely High Electrical Conductivity.

The integration of 2D graphene sheets into a porous and macroscopic structure is extremely attractive for application in several electrochemical fields. In this regard, for the first time, the synthesis of 3D graphene aerogels is reported by using a rapid, easy, cost-effective, and scalable at industrial level methodology. These aerogels integrate the intrinsic properties of graphene with a high pore volume. To achieve this ultraporous graphene network, resorcinol/formaldehyde polymer with controllable porosity is employed as a binder and a cross-linker material, and a graphene oxide solution provides the graphene building blocks. Two series of materials with and without catalyst for resorcinol/formaldehyde reaction and with different synthesis conditions and graphene contents are studied. The resulting graphene aerogels present low density, large macroporosity, and electrical conductivity values as high as 852 S m-1 , with 97.58% of porosity, which is the highest value of electrical conductivity reported so far in the literature for ultralight-weight graphene aerogels.

Structural Insights of Three 2,4-Disubstituted Dihydropyrimidine-5-carbonitriles as Potential Dihydrofolate Reductase Inhibitors.

In this report, we describe the structural characterization of three 2,4-disubstituted-dihydropyrimidine-5-carbonitrile derivatives, namely 2-{[(4-nitrophenyl)methyl]sulfanyl}-6-oxo-4-propyl-1,6-dihydropyrimidine-5-carbonitrile 1, 4-(2-methylpropyl)-2-{[(4-nitrophenyl)methyl]sulfanyl}-6-oxo-1,6-dihydropyrimidine-5-carbonitrile 2, and 2-[(2-ethoxyethyl)sulfanyl]-6-oxo-4-phenyl-1,6-dihydropyrimidine-5-carbonitrile monohydrate 3. An X-ray diffraction analysis revealed that these compounds were crystallized in the centrosymmetric space groups and adopt an L-shaped conformation. One of the compounds (3) crystallized with a water molecule. A cyclic motif (R22(8)) mediated by N-H···O hydrogen bond was formed in compounds 1 and 2, whereas the corresponding motif was not favorable, due to the water molecule, in compound 3. The crystal packing of these compounds was analyzed based on energy frameworks performed at the B3LYP/6-31G(d,p) level of theory. Various inter-contacts were characterized using the Hirshfeld surface and its associated 2D-fingerprint plots. Furthermore, a molecular docking simulation was carried out to assess the inhibitory potential of the title compounds against the human dihydrofolate reductase (DHFR) enzyme.

Supramolecular Self-Assembly Built by Weak Hydrogen, Chalcogen, and Unorthodox Nonbonded Motifs in 4-(4-Chlorophenyl)-3-[(4-fluorobenzyl)sulfanyl]-5-(thiophen-2-yl)-4H-1,2,4-triazole, a Selective COX-2 Inhibitor: Insights from X-ray and Theoretical Studies.

A selective triazole-based COX-2 inhibitor, 4-(4-chlorophenyl)-3-[(4-fluorobenzyl)sulfanyl]-5-(thiophen-2-yl)-4H-1,2,4-triazole, C19H13ClFN3S2, has been synthesized, and its crystal structure was determined at 150 K. Single-crystal X-ray diffraction analysis revealed that the thiophene ring was disordered over two orientations. The crystal structure is stabilized by weak hydrogen and chalcogen bonds and unorthodox F···π and S···C(π) contacts. These noncovalent interactions cooperatively generate the supramolecular self-assembly in the crystalline state. The Hirshfeld surface and its associated two-dimensional (2D)-fingerprint plots were obtained to analyze the role of different noncovalent interactions in the crystal packing. Further, the enrichment ratio was obtained from different atom···atom pairs to calculate the propensity of these pairs to form noncovalent interactions. The strength of different dimeric motifs formed in the crystal structure and lattice energies was calculated by the PIXEL method. Furthermore, the topological analysis of the charge density of intermolecular interactions was described. A CSD survey of C-H···F hydrogen bond, C-S···Cl chalcogen bond, and unorthodox nonbonded contacts (F···π and S···C(π)) is presented. The title compound possesses selective inhibitory activity against human COX-2 enzyme rather than COX-1. The quantum mechanics (QM) polarized ligand docking analysis was used to predict the binding pose and study the title compound's selectivity against COX-1/2 enzymes.

Sol-Gel Processing of Water-Soluble Carbon Nitride Enables High-Performance Photoanodes*.

In spite of the enormous promise that polymeric carbon nitride (PCN) materials hold for various applications, the fabrication of high-quality, binder-free PCN films and electrodes has been a largely elusive goal to date. Here, we tackle this challenge by devising, for the first time, a water-based sol-gel approach that enables facile preparation of thin films based on poly(heptazine imide) (PHI), a polymer belonging to the PCN family. The sol-gel process capitalizes on the use of a water-soluble PHI precursor that allows formation of a non-covalent hydrogel. The hydrogel can be deposited on conductive substrates, resulting in formation of mechanically stable polymeric thin layers. The resulting photoanodes exhibit unprecedented photoelectrochemical (PEC) performance in alcohol reforming and highly selective (∼100 %) conversions with very high photocurrents (>0.25 mA cm-2 under 2 sun) down to <0 V vs. RHE. This enables even effective PEC operation under zero-bias conditions and represents the very first example of a 'soft matter'-based PEC system capable of bias-free photoreforming. The robust binder-free films derived from sol-gel processing of water-soluble PCN thus constitute a new paradigm for high-performance 'soft matter' photoelectrocatalytic systems and pave the way for further applications in which high-quality PCN films are required.

Spiro[1,2]oxaphosphetanes of Nonstabilized and Semistabilized Phosphorus Ylide Derivatives: Synthesis and Kinetic and Computational Study of Their Thermolysis.

A series of tri- and tetrasubstituted spiro-oxaphosphetanes stabilized by ortho-benzamide (oBA) and N-methyl ortho-benzamide (MoBA) ligands have been synthesized by the reaction of Cα,Cortho-dilithiated phosphazenes with aldehydes and ketones. They include enantiopure products and the first example of an isolated oxaphosphetane having a phenyl substituent at C3 of the ring. Kinetic studies of their thermal decomposition showed that the process takes place irreversibly through a polar transition state (ρ = -0.22) under the influence of electronic, [1,2], [1,3] steric, and solvent effects, with C3/P-[1,2] interactions as the largest contribution to ΔG⧧ of olefination. Inversion of the phosphorus configuration through stereomutation has been observed in a number of cases. DFT calculations showed that oBA derivatives olefinated through the isolated (N, O)(Ph, C6H4, C) oxaphosphetanes (Channel A), whereas MoBA compounds decomposed faster via the isomer (C6H4, O)(C, N, Ph) formed by P-stereomutation involving a MB2 permutational mechanism (Channel B). The energy barrier of P-isomerization is lower than that of olefination. Fragmentation takes place in a concerted asynchronous reaction. The thermal stability of oxaphosphetanes is determined by strong C3/P-[1,2] interactions destabilizing the transition state of olefination. The effect of charge distribution and C3/C4-[1,2] and C4/P-[1,3] steric and solvent interactions on ΔG⧧ was also evaluated.

Advanced core-shell EDTA-functionalized magnetite nanoparticles for rapid and efficient magnetic solid phase extraction of heavy metals from water samples prior to the multi-element determination by ICP-OES.

A method for preconcentration and simultaneous determination of trace heavy metals in water media by core-shell superparamagnetic nanoparticles with the immobilized derivative of ethylenediaminetriacetic acid (referred to as MNPs/SiO2-EDTA) is proposed. The specific layer-by-layer covering of magnetite endowed the new material with essentially increased chemical stability of MNPs including acidic media and improved the affinity toward traces of toxic metal ions. The initial and modified materials were characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy, transmission and scanning electron microscopies, elemental analysis, and vibrating sample magnetometry. The obtained particles were nanodimensional with a 7-12-nm magnetic core and a 4-6-nm silica shell. The MNPs/SiO2-EDTA quantitatively removes heavy metals from contaminated media at pH ≥ 3.5 within 15 min. The adsorption data were successfully fitted to the pseudo-second-order kinetic model. The preconcentration factor was 150 and maximum adsorption capacity was 36.9 mg g-1 for Cu(II), 108.8 mg g-1 for Pb(II), 30.9 mg g-1 for Zn(II), 34.32 mg g-1 for Cr(III), and 59.5 mg g-1 for Cd(II). Due to high stability in the wide range of pH, the magnetic adsorbent can be regenerated at least six times using 0.1 M HNO3. Following adsorption/desorption, determination of metal ions is provided by inductively coupled plasma optical emission spectrometry (ICP-OES) . The linear range of the proposed method is 0.1 - 200 µg L-1. The limits of detection (LOD) are 0.12 µg L-1 for Zn(II); 0.06 µg L-1 for Cd(II); 0.39 for Cu(II); 0.15 µg L-1 for Cr(III); and 0.76 µg L-1 for Pb(II). The method performance was evaluated in the analysis of environmental, tap, and wastewater samples with recoveries in the range of 94.0-104.0%.

Synthesis, crystal structure, and thermal properties of poly[aqua-(µ5-2,5-di-carb-oxy-benzene-1,4-di-carboxyl-ato)strontium].

A coordination polymer formulated as [Sr(H2BTEC)(H2O)] n (H4BTEC = benzene-1,2,4,5-tetra-carb-oxy-lic acid, C10H6O8), was synthesized hydro-thermally and characterized by single-crystal and powder X-ray diffraction, scanning electron microscopy and thermal analysis. Its crystal structure is made up of a zigzag inorganic chain formed by edge-sharing of [SrO8] polyhedra running along [001]. Adjacent chains are connected to each other via the carboxyl-ate groups of the ligand, resulting in a double-layered network extending parallel to (100). O-H⋯O hydrogen bonds of medium-to-weak strength between the layers consolidate the three-dimensional structure. One of the carb-oxy-lic OH functions was found to be disordered over two sets of sites with half-occupancy.

Synthesis and crystal structure of 3-(adamantan-1-yl)-4-(2-bromo-4-fluoro-phen-yl)-1H-1,2,4-triazole-5(4H)-thione.

In the title compound, C18H19BrFN3S, the 1,2,4-triazole ring is nearly planar with a maximum deviation of -0.009 (3) and 0.009 (4) Å, respectively, for the S-bound C atom and the N atom bonded to the bromo-fluoro-phenyl ring. The phenyl and triazole rings are almost perpendicular to each other, forming a dihedral angle of 89.5 (2)°. In the crystal, the mol-ecules are linked by weak C-H⋯π(phen-yl) inter-actions, forming supra-molecular chains extending along the c-axis direction. The crystal packing is further consolidated by inter-molecular N-H⋯S hydrogen bonds and by weak C-H⋯S inter-actions, yielding double chains propagating along the a-axis direction. The crystal studied was refined as a racemic twin.

Impact of Co2+ Substitution on Microstructure and Magnetic Properties of CoxZn1-xFe2O4 Nanoparticles.

In the present work, we synthesized CoxZn1-xFe2O4 spinel ferrite nanoparticles (x= 0, 0.1, 0.2, 0.3 and 0.4) via the precipitation and hydrothermal-joint method. Structural parameters were cross-verified using X-ray powder diffraction (XRPD) and electron microscopy-based techniques. The magnetic parameters were determined by means of vibrating sample magnetometry. The as-synthesized CoxZn1-xFe2O4 nanoparticles exhibit high phase purity with a single-phase cubic spinel-type structure of Zn-ferrite. The microstructural parameters of the samples were estimated by XRD line profile analysis using the Williamson-Hall approach. The calculated grain sizes from XRPD analysis for the synthesized samples ranged from 8.3 to 11.4 nm. The electron microscopy analysis revealed that the constituents of all powder samples are spherical nanoparticles with proportions highly dependent on the Co doping ratio. The CoxZn1-xFe2O4 spinel ferrite system exhibits paramagnetic, superparamagnetic and weak ferromagnetic behavior at room temperature depending on the Co2+ doping ratio, while ferromagnetic ordering with a clear hysteresis loop is observed at low temperatures (5K). We concluded that replacing Zn2+ ions with Co2+ ions changes both the structural and magnetic properties of ZnFe2O4 nanoparticles.

Syntheses and crystal structures of two adamantyl-substituted 1,2,4-triazole-5-thione N-Mannich bases.

In the title N-Mannich bases, 3-(adamantan-1-yl)-4-(4-fluoro-phen-yl)-1-[(4-phenyl-piperazin-1-yl)meth-yl]-4,5-di-hydro-1H-1,2,4-triazole-5-thione (C29H34FN5S) (I), and 3-(adamantan-1-yl)-4-(4-fluoro-phen-yl)-1-{[4-(2-meth-oxyphen-yl)piperazin-1-yl]-meth-yl}-4,5-di-hydro-1H-1,2,4-triazole-5-thione (C30H36FN5OS) (II), fluoro-phenyl, adamantane and piperazine moieties are linked to a planar triazole ring. There is an additional phenyl ring on the piperazine ring in (I) and a meth-oxy-phenyl ring in (II). In compound (I), the fluoro-phenyl and phenyl rings are inclined to the triazole ring by 86.55 (13) and 60.52 (12)°, respectively, and the two aryl rings are inclined to one another by 66.37 (13)°. In compound (II), the corresponding dihedral angles are 83.35 (13), 71.38 (15) and 11.97 (16)°, respectively. The crystal structure of (I) shows pairs of C-H⋯F hydrogen bonds forming inversion dimers, while in the crystal of compound (II), in addition to the C-H⋯F hydrogen bonds that generate chains parallel to the b axis, there are C-H⋯π inter-actions present that link the chains to form layers parallel to the ab plane.