X-ray Diffraction Studies Research Articles

Synthesis and Characterization of CoFe2O4 Nanoparticles and CoFe2O4@BaTiO3 Nanocomposites for Biomedical Applications

Cobalt ferrite magnetic nanoparticles (CFO) of around 9 nm were synthesized with the solvothermal method. The CFO particles were covered with a barium titanate (BTO) shell at a 1:1 CFO:BTO ratio, via a sol-gel synthesis, to form CFO@BTO nanocomposites. X-Ray Diffraction (XRD) studies reveal the presence of only the expected CFO and BTO phases. Scanning and Transmission Electron Microscopy (SEM, TEM) images show the thorough covering with the BTO shell. Energy-Dispersive X-ray spectroscopy (EDX) mapping was used to analyze the elemental composition of the nanocomposites. Magnetic characterization shows high saturation magnetization and low coercive field at 300 K, suitable for biomedical applications.

Overcoming Ion Trapping in Chevrel Phase Compounds via Tailored Anion Substitution: An Integrated Study of Theory, Synthesis, and In Operando Techniques for Reversible Aqueous Zn-Ion Batteries.

Sustainable batteries are key for powering electronic devices of the future, with aqueous zinc-ion batteries (AZIBs) standing out for their use of abundant, readily available elements, and safer production processes. Among the various electrode materials studied for AZIBs, the Chevrel Phase, Mo6S8 has shown promise due to its open framework, but issues with zinc ion trapping have limited its practical application. In this work, we employed computational methods to investigate the insertion-deinsertion mechanism in a series of isostructural Mo6S8-xSex (x = 0-8) solid solutions as materials that could balance the gravimetric capacity and reversible cycling for AZIBs. Density functional theory (DFT) calculations revealed that increasing the Se content would reduce the binding energy of Zn within the structures, enabling Zn deinsertion compared to the Mo6S8 structure. Experiments confirmed the formation of Mo6S8-xSex (x = 0-8) solid solutions, and electrochemical testing showed improved reversibility of Zn insertion/deinsertion as the amount of Se increased, consistent with the computational predictions. Furthermore, combined in operando X-ray diffraction and electrochemical studies revealed a continuous, gradual Zn-insertion process into Mo6S4Se4, in stark contrast to the abrupt phase changes observed upon Zn insertion in Mo6S8 and Mo6Se8. DFT calculations attributed the stabilization of Zn0.5Mo6S4Se4 as a prime reason for preventing phase separation, making Se-substituted compounds promising materials for high-performance AZIBs. Overall, this interdisciplinary approach, integrating computational modeling, materials synthesis, and advanced characterization techniques, offers a pathway for fine-tuning anion chemistry that can help create high-performance electrode materials for sustainable energy storage technologies.

Exploring the potential of metal tailored imine based covalent organic framework for asymmetric supercapacitor applications

Currently, a fascinating area of research involves the development of stable and efficient materials for energy storage systems. The current work describes the synthesis of imine linked covalent organic framework (COF) using 4,4′,4′',4′''-(ethene-1,1,2,2-tetrayl) tetraaniline and terephthalaldehyde (TAT-COF) as precursors through solvothermal method. In addition, cobalt has been integrated to the imine linkage of TAT-COF to generate CO@TAT-COF. The X-ray diffraction study reveals the formation of ordered and crystalline TAT-COF with eclipsed (AA) stacking configuration. Morphological characterization indicated the accumulation of metal species over stick like structured TAT-COF. Energy-dispersive X-ray (EDX) and Fourier Transform Infrared Spectroscopy results shows the successive intercalation of Co to the TAT-COF matrix. TAT-COF and Co@TAT-COF were examined towards electrochemical performance for supercapacitor applications. A two fold higher specific capacitance (Csp) was obtained in Co@TAT-COF (637 F/g) compared to TAT-COF (315 F/g) at 5 mV/s scan rate. The Co@TAT-COF showed an energy density (ED) of 58 Wh/kg at a power density of (PD) of 1500 W/kg. Enhanced electrochemical performance in Co@TAT-COF could be attributed to the structural confinement, conductivity, enhanced interlayer spacing and porosity. Co@TAT-COF has been used as positive electrode to fabricate an asymmetric device (ASD) in using Swagelok cell. The Csp of the fabricated ASD was found to be 95 F/g at 2 mV/s scan rate. ASD showed good stability with 73 % retention of Csp over 5000 charge/discharge cycles. The obtained results indicate the suitability of the engineered COFs towards energy storage devices.

Pyrazolone-Based Zn(II) Complexes Display Antitumor Effects in Mutant p53-Carrying Cancer Cells.

The synthesis and characterization of nine Schiff bases of pyrazolone ligands HLn (n = 1-9) and the corresponding zinc(II) complexes 1-9 of composition [Zn(Ln)2] (n = 1-9) are reported. The molecular structures of complexes 2, 3, 4, 8, and 9 were determined by single-crystal X-ray diffraction analysis, highlighting in all cases a distorted tetrahedral geometry around the Zn(II) ion. Density functional theory studies are performed on both the HLn ligands and the derived complexes. A mechanism of dissociation and hydrolyzation of the coordinated Schiff base ligands is suggested, confirmed experimentally by powder X-ray diffraction study and photophysical studies. Complexes 1-9 were investigated in vitro as anticancer agents, along with mutant p53 (mutp53) protein levels in human cancer cell lines carrying R175H and R273H mutp53 proteins. Only those complexes with the highest Zn(II) ion release via dissociation have shown a significant cytotoxic activity with reduction of mutp53 protein levels.

Self-Assembled Lanthanide Phosphinate Square Grids (Ln = Er, Dy, and Tb): Dy4 Shows SMM/SMT and Tb4 SMT Behavior.

Tetranuclear [2 × 2] square-grid-like LnIII clusters have been synthesized by reacting LnCl3·6H2O salts with bis[α-hydroxy(p-bromophenyl)methyl]phosphinic acid [R2PO2H, where R = CH(OH)PhBr] and pivalic acid. Single-crystal X-ray diffraction studies show the formation of [Me4N]2[Ln4(μ2-η1:η1-PO2R2)8(η2-CO2But)4(μ4-CO3)] [Ln = Er (1), Dy (2), and Tb (3)]. Direct-current studies reveal significant ferromagnetic interactions between DyIII in 2 and TbIII in 3 and an antiferromagnetic interaction between ErIII in 1. Dynamic magnetic susceptibility measurements confirm a single-molecule magnet (SMM) behavior in both 0 and 1200 Oe applied magnetic fields for 2. Complexes 2 and 3 show single molecular toroic (SMT) behavior with a mixed magnetic moment.

Promising ferroelectric and piezoelectric response of Cr-doped ZnO nanofiller-incorporated PVDF flexible and laminated nanocomposite system.

Cr3+-doped ZnO (CZ) nanoparticles are prepared using hydrothermal and co-precipitation techniques. The desired crystallographic phase of the nanoparticles is confirmed using X-ray diffraction study. Rod-shaped and spherical morphologies of CZ nanoparticles prepared using hydrothermal and co-precipitation techniques were confirmed through FESEM observation. Each type of nanoparticle was taken separately in PVDF to understand the characteristic properties, such as dielectric, piezoelectric, and ferroelectric properties of the resultant CZ-PVDF nanocomposite films. All the nanocomposite films comprising rod-shaped or spherical CZ nanoparticles show butterfly loops with a low leakage current density of 10-5 A m-2 at a maximum electric field of 100 kV m-2 under J-E measurement. These findings suggest that the polarization property of CZ-PVDF nanocomposite films can be obtained at a high external electric field without causing electric breakdown in the samples. Dielectric permittivity as a function of temperature increases with an increase in the loading percentage of both rod-shaped or spherical CZ nanofillers in PVDF. Polarization response also improves with an increase in the loading percentage of CZ nanofillers in PVDF. In particular, the rod-shaped CZ nanofillers in PVDF with a higher loading percentage (CZHP2) result in a maximum polarization of (10 ± 0.29) × 10-4 μC cm-2, remanent polarization of (2 ± 0.04) × 10-4 μC cm-2, and coercive field of (10 ± 0.1) kV cm-1 at a maximum electric field of 50 kV cm-1. The CZHP2 nanocomposite film has a piezoelectric coefficient (d33) of (25 ± 0.24) pC N-1 and a power density of 1278.90 W m-3. These results indicate that the nanocomposite films have potential application in piezoelectric energy harvesters, offering a possible solution to the energy issue faced by modern society.

Sustainable building envelopes: Evaluating the thermal performance of thatched roofs fabricated using coconut leaves

Excessive heat gain in residential buildings during sunny days, especially in tropical regions, leads to increased reliance on active energy cooling systems, contributing to higher carbon emissions and energy costs. Traditional roofing materials, such as terracotta tiles are often insufficient in mitigating indoor temperature rise, necessitating the exploration of alternative, sustainable solutions. This study investigates the thermal performance of naturally available coconut leaves used as thatch roofing, comparing it with conventional terracotta tiles, to determine their effectiveness in controlling interior temperatures and reducing heat gain in buildings. To mitigate such a problem, the Near Infra-Red (NIR) light reflectivity of dried plant leaves derived from deciduous and coniferous trees was measured. The structural hierarchy of the leaves was confirmed through Field Emission Scanning Electron Microscope (FESEM), Fourier Transform Infrared Spectroscope (FTIR) and X-ray Diffraction (XRD) studies. FTIR spectra reveal characteristic vibrations of ester, cellulosic components, etc., and XRD confirms the amorphous status of cellulosic materials present in the plant biomass. To study the use of thatched roofs made using coconut leaves as a roofing element, two test huts were fabricated - one was covered using terracotta roof tiles and the other was covered using coconut leaves thatches. The thermal performances of two roofing materials were recorded on a sunny day and the results were compared. The temperature data noticed reveal the fact that the maximum average surface temperature of the terracotta roof model was 59.53 °C, while the rooftop covered with coconut thatches exhibits a temperature of 54.26 °C which is 8.8% less than the hut covered with terracotta tiles. The interior temperature recorded in the coconut thatch was 33.36 °C, which was 1.15 °C lower (34.51 °C) than the terracotta tiles-covered test hut, confirming the better thermal comfortability of thatched roof model than a terracotta roof model.

Hydrothermal synthesis, characterization of Co3Sb4O6F6 and carbon doped Co3Sb4O6F6 and their application towards photocatalytic dye degradation, adsorption, catalytic Knoevenagel condensation and bacterial disinfection

Single crystals of Co3Sb4O6F6 have been grown by employing hydrothermal techniques. Table sugar was utilized to prepare carbon-doped Co3Sb4O6F6. The objective was to employ Co(II)-based metal oxyfluoride comprising a stereochemically active lone pair element (Sb3+) and its carbon-doped analogues for the multifunctional applications. The impact of carbon doping on Co3Sb4O6F6 has been evaluated towards the changes in photocatalytic, catalytic, and adsorbent efficiency. The changes in carbon percentage affect the physical and chemical properties of the host material. A larger percentage of carbon doping turns the photocatalytic ability of the host material into an adsorbent for the removal of dye. The single crystal X-ray diffraction study reveals that Co3Sb4O6F6 crystallizes into cubic symmetry. However, powder X-ray diffraction study reveals the structural transformation in the carbon-doped Co3Sb4O6F6. It also reduces the band gap energy of the host material, and 4 wt% C@Co3Sb4O6F6 turns out to be an efficient photocatalyst. Large-scale carbon doping (15 wt%) appears to be an effective strategy to increase the surface charge and BET surface area, as consequences adsorption property develops in 15 wt% C@Co3Sb4O6F6/H2O2 for the elimination of methylene blue (MB). This favourable chemical adsorption process occurs with large maximum adsorption capacity (qmax = 58.41169 mg g-1), as evident from the Langmuir adsorption isotherm. Scavenger experiment confirms that the photocatalytic activities of the as-synthesised compounds were triggered by the active participation of the hydroxyl radical (.OH). The catalytic efficiencies of both parent and doped compounds are also established for the solvent-free Knoevenagel condensation reaction with 90 % yield at moderate temperature. Bacterial disinfection studies by the ‘Disc diffusion method’ confirm that Co3Sb4O6F6 shows better efficiency than the carbon doped compound against both Gram-positive and Gram-negative bacteria.

Electromagnetic interference shielding properties of PMMA modified-Co0.5Zn0.5Fe2O4 − polyaniline composites

Present work reports solution combustion synthesis (SCS) of Co0.5Zn0.5Fe2O4 spinel ferrite, its chemical modification with polymethylmethacrylate (PMMA), synthesis of polyaniline (PANI), and electromagnetic interference (EMI) shielding properties of their composites. Both as-prepared and PMMA-modified Co0.5Zn0.5Fe2O4 adopt cubic spinel structure as shown by X-ray diffraction studies. Field emission scanning electron microscopy images show the agglomerated and microporous nature of the ferrites. High resolution transmission electron microscopy image of as-prepared Co0.5Zn0.5Fe2O4 shows lattice fringes related to (311) plane of the spinel structure. X-ray photoelectron spectroscopy studies reveal the presence of Co2+, Zn2+, and Fe3+ in tetrahedral and octahedral coordinations in the ferrite. EMI shielding properties are evaluated for PMMA-modified Co0.5Zn0.5Fe2O4 and PANI composites in different weight ratios. Composites containing PMMA-modified ferrite and PANI with 50:50 and 10:90 weight ratios show the best performance among all the composites in 2−20 GHz frequency range. Optimized PMMA-modified Co0.5Zn0.5Fe2O4 and PANI composite with the ratio of 10:90 shows shielding effectiveness (SE) values of −16.6 to −24.2 dB in 2−20 GHz frequency region.Graphical

DNA/BSA Binding and Antimicrobial Properties of Biguanide-Cu(II) Complexes.

The biguanide Cu(II) complexes [Cu(L1-4)2](ClO4)2 were synthesized and spectroscopic/analytical techniques were used to clarify their structures. Single crystals of complex [Cu(L4)2](ClO4)2 was obtained and its definite structure was determined by single crystal X-ray diffraction study. The complexes [Cu(L1-4)2](ClO4)2 were screened for their FSds-DNA interactions by using UV-Vis absorption and fluorescence spectroscopies. The complexes [Cu(L2)2](ClO4)2 and [Cu(L3)2](ClO4)2 were shown to exhibit higher affinity for binding DNA. Examining the EB-DNA interaction, it is believed that the complexes interact with DNA through a groove binding mechanism. The interaction of complexes with BSA were observed through the quenching of the fluorescence emission. Complexes [Cu(L2)2](ClO4)2 and [Cu(L3)2](ClO4)2 show moderate binding affinity to BSA through a static mode. Additionally, the Cu(II) complexes were screened for their antibacterial activities against various bacterial strains. Complexes showed potential antimicrobial activity against Salmonella typhimurium, Bacillus cereus, Salmonella typhimurium and S. aureus.

Influence of local structure and metal-oxygen hybridization on the electrical and magnetic properties of alkaline earth metal (Mg2+, Ca2+, Sr2+) substituted LaFeO3 ceramics

Pristine and alkaline-earth metal-substituted LaFeO3 (La1−xAxFeO3−δ; x = 0 and 0.2; A = Mg2+, Ca2+, and Sr2+) sintered ceramics are prepared from nanoparticles synthesized via a low-temperature citrate sol–gel technique. X-ray diffraction studies confirm the formation of a phase-pure LaFeO3 structure without any secondary phases for all the La1−xAxFeO3−δ compositions. LaFeO3 and La0.8Mg0.2FeO3−δ ceramics show Raman active modes related to La vibration, oxygen octahedral tilting, bending, and stretching. The optical bandgap is estimated to be 2.34 eV for pure LaFeO3 and reduces to 2.23 eV for La0.8Mg0.2FeO3−δ ceramics. On the contrary, La0.8Ca0.2FeO3−δ and La0.8Sr0.2FeO3−δ ceramics show no features in Raman spectra, consistent with the observation of metallic nature and diffuse band edge without any indication of sharp band edge noted. X-ray absorption spectroscopy (XAS) studies on La-L3 and Fe-K-edges confirm the oxidation states of La3+ and Fe3+ in all these ceramics. Local structural distortions and formation of oxygen vacancies in La0.8A0.2FeO3−δ (A = Mg2+, Ca2+, and Sr2+) ceramics are discerned from XAS structure analysis compared to the pristine LaFeO3 ceramics. Magnetic measurements of La1−xAxFeO3−δ reveal weak ferromagnetic nature except for La0.8Mg0.2FeO3−δ, which shows a large magnetization of 4.6 (6.7) emu/g at 300 (5) K. The ferromagnetic behavior of La0.8Mg0.2FeO3−δ ceramics seems to originate from the modification of hybridization between Fe(3d)–O(2p), La(5d)–O(2p), and Fe(4sp)–O(2p) orbitals. An anomalous magnetic transition observed only in zero-field-cooled curves at 88 K in La0.8Ca0.2FeO3−δ and La0.8Sr0.2FeO3−δ ceramics is correlated to the formation of new electronic states containing O 2p character as discerned from pre-peak O-K-edge.

Aromatic (co)polycarbonates bearing pendant 2,3-dimethylmaleimido group based upon a new phthalimidine-containing “cardo” bisphenol

A new “cardo” bisphenol viz., 1-(2-(1,1-bis(4-hydroxyphenyl)-3-oxoisoindolin-2-yl)ethyl)-3,4-dimethyl-1H-pyrrole-2,5-dione (PPH-MA) was synthesized in a two-step reaction sequence starting from phenolphthalein. PPH-MA was utilized as a step-growth monomer for the synthesis of a homo- and fourco-polycarbonates bearing pendant 2,3-dimethylmaleimido groups (PC-MAs) via solution polycondensation of PPH-MA or various mol % compositions of PPH-MA and bisphenol-A, respectively, with triphosgene.1H NMR spectroscopy confirmed the chemical structure and composition of PC-MAs. Inherent viscosity and number average molecular weight values of PC-MAs were in the range 0.45–0.64 dL g−1 and 18,300 − 36,200 g mol−1, respectively, indicating the formation of polymers of medium to reasonably high molecular weights. Tough, transparent and flexible films of PC-MAs could be cast from chloroform solution. X-ray diffraction studies indicated the amorphous nature of PC-MAs. The 10% weight loss temperature (T10) values of PC-MAs were in the range 373–443 °C indicating their good thermal stability.

Vachelia nilotica seed-mediated green synthesis of sulfur nanoparticles (SNPs) and evaluation of anticancer & antifungal activities

Sulfur nanoparticles (SNPs) have been successfully synthesized by applying Vachelia nilotica seed extract as a bioactive aqueous material by a disproportionation reaction of sodium thiosulfate pentahydrate (Na2S2O3 .5H2O) with a 10% hydrochloric acid (HCl) at room temperature. The synthesized SNPs were characterized by UV–Visible, Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy-Dispersive X-ray Spectroscopy (EDS), and X-ray Diffraction (XRD) techniques. The usual size of SNPs was determined by an XRD study and calculated with the Debye–Scherrer formula. The SNPs are crystalline with a calculated average size of 45 nm. The SEM and TEM analyses revealed spherical shape and size around 55 nm of SNPs. The synthesized SNPs were screened for their antifungal activity against M. furfur species and for anticancer activities against (MCF-7, HepG2) cell lines. The obtained results suggested towards moderate to good antifungal and excellent anticancer activities.

Novel CdFe2O4 nanoparticles facile synthesis and their applications towards practical ammonia detection: an effect of annealing

Cadmium ferrite (CdFe2O4) nanoparticles were synthesized via a simple co-precipitation method, and the effect of annealing temperature over the prepared samples’ structural, morphological, and optical properties was analyzed by varying the temperatures 700, 800, and 900 °C. The x-ray diffraction (XRD) studies revealed that the prepared samples are highly crystalline in nature and belong to a cubic spinel crystal structure, and the crystallite size increases from 32 to 59 nm with respect to the increasing temperature. The surface morphology of the ferrite samples showed the uniformly distributed highly agglomerated particles with larger voids for the ferrite nanoparticles annealed at 900 °C. Optical properties of the prepared CdFe2O4 samples were carried out by diffused reflectance spectroscopy (DRS) and the optical band gap of the samples were found to be 2.57, 2.55 and 2.53 eV. The Vibrating sample magnetometer (VSM) studies at room temperature showcased that the nanoparticle samples possess ferromagnetic behavior, and the magnetization (Ms), Coercivity (Hc), and Retentivity (Mr) values were found to be 27.5 × 10−3 emu g−1, 237.60 Oe, and 1976 × 10−6 emu/g for the CdFe2O4 sample annealed at 900 °C. The gas sensing studies were carried out with the presence of target gas ammonia, and its significant sensing parameters such as gas responsivity (S%), rise time, and recovery times were determined, and these values of CdFe2O4 samples annealed at 900 °C were observed to be 1610%, 7.1 s, and 2.2 s. Our findings strongly suggest that the CdFe2O4 samples annealed at 900 °C hold significant promise as a multifunctional material, particularly in gas-sensing applications. This potential opens an exciting avenue for further research and development.

Synthesis, crystal structure, DNA/protein interactions and cytotoxicity studies of tridentate ligand based Cu(II) complexes with various amine co-ligands

The present study utilizes a tridentate ligand H2L (1) derived as a condensation product of dehydroacetic acid and 2-furoic acid hydrazide for the synthesis of a series of copper complexes, namely [Cu(L)(bipy)] (3), [Cu(L)(4,4′-Me2-bipy)] (4), [Cu(L)(6,6′-Me2-bipy)] (5), [Cu(L)(phen)] (6), [Cu(L)(2,9-Me2-phen)] (7) [Cu(L)(pyrazino[2,3]phen)] (8) [Cu(L)(2,2′-dipyridylamine)] (9) [Cu(L)(diphenylmethanamine)] (10), obtained by reacting Cu(acetate)2 with the doubly deprotonated ligand and a range of co-ligand amines. All the synthesized compounds were fully structurally characterized using IR, 1H NMR, HRMS and single-crystal X-ray diffraction studies. The thermal stability and decomposition pattern was investigated using TGA studies. The bio-efficacy of the developed ligand and its complexes was evaluated in anti-cancer assay against SKOV3 cell lines. Copper complexes have been extensively studied for their potential to generate anticancer properties. Most complexes comprise mixed ligands, such as N-N-chelating heterocycles like 2,2’-bipyridine (bpy) and 1,10 phenanthroline (phen), chosen for their chelating and intercalative characteristics. Complex 7 displayed the highest anti-cancer activity with an IC50 value of 0.8 µM compared to standard drug doxorubicin. The impact of complex 7 on DNA fragmentation was also assessed through agarose gel electrophoresis, which indicated that complex 7 promotes observable DNA fragmentation. The serum binding affinity of the complex 7 was also investigated against BSA and HSA protein. The strong binding affinity of complex [Cu(L)(2,9-Me2-phen)] (7) with BSA/HSA and its better stability compared to the other investigated complexes were deduced based on its biological activity. The impact of varying concentrations of complex 7 on BSA and HSA was investigated using absorption spectroscopy, revealing the presence of a dynamic quenching mechanism. In silico molecular dynamics and docking, approaches have been utilized to validate the empirical data derived from serum binding studies.

High Milling Time Influence on the Phase Stability and Electrical Properties of Fe50Mn35Sn15 Heusler Alloy Obtained by Mechanical Alloying.

Fe50Mn35Sn15 Heusler alloy, obtained by mechanical alloying, was subjected to larger milling times in the range of 30-50 h to study the phase stability and morphology. X-ray diffraction studies have shown that the milled samples crystallise in a disordered A2 structure. The A2 structure was found to be stable in the milling range studied, contrary to the computation studies performed on this composition. Using Rietveld refinements, the lattice parameter, mean crystallite size, and lattice strain were computed. The nature of the obtained phases by milling was found to be nanocrystalline with values below 50 nm. A linear increase rate of 0.00713 (h-1) was computed for lattice strain as the milling time increased. As the milling time increases, the lattice parameter of the cubic Heusler was found to have a decreasing behaviour, reaching 2.9517 Å at 50 h of milling. The morphological and elemental distribution-characterised by scanning electron microscopy and energy-dispersive X-ray spectroscopy-evidenced Mn and Sn phase clustering. As the milling time increased, the morphology of the sample was found to change. The Mn and Sn cluster size was quantified by elemental line profile. Electrical resistivity evolution with milling time was analysed, showing a peak for 40 h of milling time.

Mononuclear nickel(II) and copper(II) coordination compounds with ligands based on acetyl(benzoyl)acetone S-methylisothiosemicarbazones and 8-quinolinecarboxaldehyde. Synthesis and crystal structure

Template condensation of S-methylisothiosemicarbazones of acetyl- or benzoylacetone with 8-quinolinecarboxaldehyde in the presence of nickel(II) and copper(II) ions gave four new mononuclear coordination compounds [NiL1]I (I), [CuL1I] (II), [NiL2]I (III) и [CuL2I] (IV). The chemical composition of the products was confirmed by elemental analysis, IR spectroscopy, and mass spectrometry, and the crystal structure of compounds I and II was determined by X-ray diffraction analysis (CCDC no. 2266386, 2266387). X-ray diffraction study revealed a square planar coordination environment of the central ion of the cationic Ni(II) complex and square pyramidal geometry for the molecular Cu(II) complex.

In situ synchrotron X-ray diffraction study: Phase evolution in transition zone of TiAl/Ti2AlNb dual alloy fabricated by laser-directed energy deposition

The phase evolution in the transition zone (TZ) of TiAl/Ti2AlNb dual alloy during laser-directed energy deposition (L-DED) process was investigated using in situ synchrotron radiation X-ray diffraction. The as-solidified microstructure of the TZ forms through the following phase transitions: Liquid→ Liquid + β/B2 →β/B2→ β/B2 + α2. Thermal cycles promote the β/B2 to α2 phase transition with the α2 phase precipitates from the (011) plane of the β/B2 matrix during this transition. The phase transition sequence of the TZ during the first thermal cycle is: β/B2 + α2 → β/B2 → β/B2 + α2. The second thermal cycle leads to a partial transformation of β/B2 phase to α2 phase. The TZ experiences no phase transition from the third thermal cycle. This study provides a comprehensive understanding of the phase formation mechanism in the TZ of L-DEDed TiAl/Ti2AlNb dual alloys.

Synthesis and study of structural, electric, and dielectric behavior of La0.5Sm0.2Sr0.3Mn1-xFexO3 perovskite

In this study, the synthesized samples La0.5Sm0.2Sr0.3Mn1-xFexO3 (x = 0.05, 0.15 and 0.20) were thoroughly investigated for their crystalline structure, electrical conductivity, and dielectric properties, the samples were prepared using autocombustion method. According to the X-ray diffraction study, the samples crystallized in an orthorhombic symmetry with the Pnma space group. To measure the dielectric characteristics, impedance spectroscopy was conducted over the temperature range of 100–260 K and a frequency range of 100 Hz to 1 MHz. Measurements of AC conductivity are indeed utilized to investigate the transport properties of materials being studied. The results indicated that both temperature and frequency significantly influence the conduction process. Three theoretical hypotheses were proposed to explain the hopping conduction: overlapping large polaron tunneling (OLPT), the non-overlapping small polaron tunneling (NSPT) mechanism, and correlated barrier hopping (CBH). It is also shown that the conductivity diminishes with an increase in Fe content. La0.5Sm0.2Sr0.3Mn1-xFexO3 (x = 0.05, 0.15 and 0.20) can be used in electronic applications because of the high permittivity values confirmed by the dielectric measurements. With the aim of evaluating the distinct impacts of electrodes, grain boundaries, and grains on the complex impedance results, an appropriate alternative electrical circuit was utilized. Analysis of the sample's modulus indicated non-Debye characteristics and electrical relaxation phenomena. The materials exhibit good electrical properties, as well as strong chemical and thermal stability.

Two rhombic-shaped Ln4 clusters for efficiently catalyzing CO2 cycloaddition and knoevenagel condensation

Two Ln4 clusters with the formula of [Ln4(acac)4(µ3OH)2(L)6]·xCH3CN (Ln=Sm (1), Yb (2)) were synthesized through the reaction of Ln(acac)3·2H2O (Hacac = acetylacetone) with the bidentate flexible ligand 5-benzylidene-1,5-dihydroquinolin-8-ol. X-ray diffraction studies indicate that clusters 1 and 2 are isostructural and processes a rhombic-shaped Ln4 core. The coordination geometry of each Ln(III) ion is characterized as a distorted square antiprism. Notably, clusters 1 and 2 exhibit outstanding catalytic performance for the cycloaddition of CO2 with epoxides and for Knoevenagel condensation under mild conditions.