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A superhard carbon phase with Pmmm (D2h1, 47) symmetry is predicted by using a recently developed particle swarm optimization method for searching for crystal structures. The carbon phase is an orthorhombic crystal system that contains 16 atoms per unit cell, named oC16, which has an all-sp3-hybridized bonding network and contains a large cavity. oC16 has a distinct topology, including zigzag four-, five-, six-, and eightfold carbon rings. The dynamic, elastic, and electronic properties of oC16 are investigated by first-principles calculations, and the results show that oC16 is more energetically stable than the experimentally synthesized T-carbon, BC8, and BC12. The phonon spectra and elastic constants confirm its dynamical and mechanical stability at zero pressure, respectively. The calculated bulk moduli and hardness indicate that oC16 is an ultra-incompressible and superhard material. Analyzing its electronic band structure reveals that oC16 has insulation characteristics with an indirect bandgap of 4.42 eV. Also investigated is how the elastic moduli of the oC16 phase depend on the crystal orientation. Because of its superhard and porous properties, the potential uses of oC16 include hydrogen storage, molecular sieves, coating, and tools for cutting, polishing, and grinding. [ABSTRACT FROM AUTHOR]

The present work elucidates the fabrication of Barium Lanthanum Oxide nanosheets (BaLa2O4 NSs) via a simple one-pot precipitation method. The acquired results show an orthorhombic crystal system with an average crystallite size of 27 nm. The morphological studies revealed irregular-shaped sheets stacked together in a layered structure, with the confirmation of the precursor elements. The diffused reflectance studies revealed a strong absorption between 200 nm and 350 nm, from which the band-gap energy was evaluated to be 4.03 eV. Furthermore, the fluorescence spectrum was recorded for the prepared samples; the excitation spectrum shows a strong peak at 397 nm, attributed to the 4F7/2→4G11/2 transition, while the emission shows two prominent peaks at 420 nm (4G7/2→4F7/2) and 440 nm (4G5/2→4F7/2). The acquired emission results were utilized to confirm the color emission using a chromaticity plot, which found the coordinates to be at (0.1529 0.1040), and the calculated temperature was 3171 K. The as-prepared nanosheets were utilized in detecting latent fingerprints (LFPs) on various non-porous surfaces. The powder-dusting method was used to develop latent fingerprints on various non-porous surfaces, which resulted in detecting all the three ridge patterns. Furthermore, the as-synthesized nanosheets were used to degrade methyl red (MR) dye, the results of which show more than 60% degradation at the 70th minute. It was also found that there was no further degradation after 70 min. All the acquired results suggest the clear potential of the prepared BaLa2O4 NSs for use in advanced forensic and photocatalytic applications. [ABSTRACT FROM AUTHOR]

Acousto-optic (AO) interaction in optically biaxial crystals is of great interest due to the variety of phase matching geometries caused by the low symmetry of the acoustic, optical, and photoelastic properties. The current state of the research in the field of acousto-optics of biaxial crystals is presented. Some promising biaxial crystals of the orthorhombic and monoclinic systems, which are of practical interest as materials for AO devices, are considered. The unique geometries of isotropic and anisotropic diffraction that exist in only biaxial crystals are analyzed, and the AO devices based on these crystals are briefly reviewed. [ABSTRACT FROM AUTHOR]

This study systematically investigates the molecular structure and electronic properties of 2-methoxy-4,6-diphenylnicotinonitrile, employing X-ray diffraction (XRD) and sophisticated computational methodologies. XRD findings validate the compound's orthorhombic crystallization in the P21212 space group, composed of a pyridine core flanked by two phenyl rings. Utilizing the three-dimensional Hirshfeld surface, the research decodes the molecule's spatial attributes, further supported by exhaustive statistical assessments. Key interactions, such as π–π stacking and H⋯X contacts, are spotlighted, underscoring their role in the crystal's inherent stability and characteristics. Energy framework computations and density functional theory (DFT) analyses elucidate the prevailing forces in the crystal and reveal geometric optimization facets and molecular reactivity descriptors. Emphasis is given to the exploration of frontier molecular orbitals (FMOs), aromaticity, and π–π stacking capacities. The research culminates in distinguishing electron density distributions, aromatic nuances, and potential reactivity hotspots, providing a holistic view of the compound's structural and electronic landscape. Concurrently, molecular docking investigates its interaction with the lipoprotein-associated phospholipase A2 protein. Notably, the compound showcases significant interactions with the protein's active site. Molecular dynamics simulations reveal the compound's influence on protein stability and flexibility. Although the molecule exhibits strong inhibitory potential against Lp-PLA2, its drug development prospects face challenges related to solubility and interactions with drug transport proteins. [ABSTRACT FROM AUTHOR]

The new compound 4-hydroxy-1-[(4-nitrophenyl)sulfonyl]pyrrolidine-2-carboxyllic acid was obtained by the reaction of 4-hydroxyproline with 4-nitrobenzenesulfonyl chloride. The compound was characterized using single crystal X-ray diffraction studies. Spectroscopic methods including NMR, FTIR, ES-MS, and UV were employed for further structural analysis of the synthesized compound. The title compound was found to have crystallized in an orthorhombic crystal system with space group P212121. The S1-N1 bond length of 1.628 (2) Å was a strong indication of the formation of the title compound. The absence of characteristic downfield 1H NMR peak of pyrrolidine ring and the presence of S–N stretching vibration at 857.82 cm−1 on the FTIR are strong indications for the formation of the sulfonamide. The experimental study was complemented with computations at the B3LYP/6-311G + + (d,p) level of theory to gain more understanding of interactions in the compound at the molecular level. Noncovalent interaction, Hirsfeld surface analysis and interaction energy calculations were employed in the analysis of the supramolecular architecture of the compound. Predicted ADMET parameters, awarded suitable bioavailability credentials, while the molecular docking study indicated that the compound enchants promising inhibition prospects against dihydropteroate synthase, DNA topoisomerase, and SARS-CoV-2 spike. Herein we present the solid state structure, noncovalent interaction and spectroscopic analysis of a prospective bioactive compound 4-hydroxy-1-[(4-nitrophenyl)sulphonyl]pyrrolidine-2-carboxyllic acid. [ABSTRACT FROM AUTHOR]

A systematic study of the phase composition of quenched binary titanium alloys with d-metals of groups 5–11 from periods four to six was carried out using the methods of X-ray diffraction analysis. It was found that the formation of the orthorhombic α″-phase depends on the position of the alloying metal in the periodic table. The formation of the α″-phase occurs only in the systems Ti-V, Ti-Nb, Ti-Mo, Ti-Ru, Ti-Ta, Ti-W, Ti-Re, Ti-Os and Ti-Ir, and in other systems, it does not occur. It was found that the critical parameter for the formation of the α″-phase is the difference in the size of titanium atoms and those of the alloying metal {(rTi − rMe)/rTi 100%}. The formation of the α″-phase occurs only in systems where this value is lower than 9 at.%. [ABSTRACT FROM AUTHOR]

Tn this study, Tn-doped MoO3 nanobelts were synthesized using a hydrothermal method to investigate the effects of Tn doping concentration on their physical phase, morphology, and room-temperature hydrogen sensing properties. The results revealed that the Tn-doped products were orthorhombic MoOs nanobelts with an average length of approximately 5/im and a diameter of about 200 nm. As the Tn-doping concentration increased from 2 to 6 at %, the room-temperature hyd rogen sensing properties of the nanobelts were gradually enhanced. However, the properties deteriorated when the Tn-doping concentration was further increased to 1 Oat%. The MoO3 nanobelts with a doping concentration of 6at % exhibited the best room-temperature hydrogen sensing performance, with a response of approximately 1.84 to 3000 ppm H2 and a response time of about 42 s. Moreover, the Tn-doped MoO3 nanobelts showed good repeatability to hydrogen and exhibited excellent selectivity and stability. [ABSTRACT FROM AUTHOR]

Herein we report, an efficient red-emitting phosphor Ca 3 Ga 4 O 9 :Eu3+ (Eu3+: CGO) was synthesized via a conventional solid-state reaction technique. The physicochemical properties of the given oxide phosphors were investigated in terms of structural, elemental, compositional, and optical characteristics. The XRD study indicates that the compound CGO and Eu3+: CGO have been crystallized in an orthorhombic crystal system with the space group of Cmm2. The nature of the oxidative state of the elements and their compositional ratios were demonstrated by the XPS and EDS studies. The SEM analysis of the phosphor samples reveals micro flakes embedded in rod-like morphology. UV–Visible diffuse reflectance studies were performed to study the optical properties of the oxide phosphors. The optical energy gap value has been calculated using Kubelka-Munk equations and the values have a reducing trend due to the addition of the Eu3+ ion. The photo-emissive properties of the Eu3+ doped samples were illustrated by the PL analysis with the excitations of 465 nm and 394 nm (7F 0 -5D 2 and 7F 0 -5L 6) respectively. The photometric (color coordinates, color purity, and correlated color temperature) parameters were also calculated. The Eu3+ doped samples show a high color purity within the range of 96.75–98.71%. The correlated color temperature (CCT) was also computed from the calculations which have the values from 1819 K to 1898 K. These results depict that the prepared Eu3+ ions doped oxide phosphor will be an efficient red-emitting candidate for white LED application. [ABSTRACT FROM AUTHOR]

The title compound is synthesized, and characterized by spectroscopic and XRD methods. The compound crystallizes in the orthorhombic crystal system with the space group P212121. The structure exhibits C–H⋯N intermolecular interaction and π⋯π interactions. Hirshfeld surface analysis was performed to determine the individual contributions of intermolecular contacts to the crystal packing. The structural and electronic properties of the molecule were investigated by density functional theory method with B3LYP hybrid functional. Intramolecular interactions involved in the crystal structure was analyzed through topological atom-in-molecules analysis and noncovalent interactions method. Molecular electrostatic potential surface shows the chemical reactive regions around the nitrogen and hydrogen atoms. The article presents the characterization of synthesized compound by single crystal X-ray diffraction method. Atom-in-molecules analysis and noncovalent interactions Intramolecular interactions involved in the crystal structure were analyzed by DFT method. [ABSTRACT FROM AUTHOR]

In this paper, detailed studies of structural, micro-structural, dielectric, electrical and magneto-electric characteristics of chemically synthesized a new double perovskite, BiSrFeCeO6 (strontium cerate-modified bismuth ferrite), are reported. The basic crystal data (unit cell dimension and orthorhombic crystal system) of the compound were obtained by analysing the room temperature X-ray powder diffraction data. Study of the surface microstructure of a sintered pellet sample, recorded by scanning electron microscope at room temperature, reveals the formation of high-density sample with the homogeneously and uniformly distributed grains of different size and shape. Analysis of frequency-temperature dependence of dielectric parameters and nature of hysteresis loop has exhibited the ferroelectric characteristics of the material. Studies of complex impedance and modulus components at different temperatures and frequencies have provided electrical characteristics of grains and grain boundaries present in the material, which are closely related to its microstructure. Thus, the correlation between the crystal structure with electrical properties and relaxation mechanism of the prepared sample has been established. The type of dielectric relaxation process and mechanism occurred in the compound have also been studied not only by analysis of the dielectric properties (εr, tan δ) and impedance parameters, but also from the study of frequency-temperature conductivity. The existence of negative temperature coefficient of resistance (NTCR) characteristics in the material has been confirmed from the temperature and dc conductivity analysis. Similarly, the frequency and ac conductivity analysis show that the studied compound follows Jonscher's universal power law. Based on the structural, ferroelectric, magnetic and magneto-electric characteristics, multiferroism in the new composition of bismuth ferrite has been established. [ABSTRACT FROM AUTHOR]

The grossular garnet from rodingite-type rock from the Suva Česma area in western Serbia is characterized with its weak anisotropic nature. Because its anisotropy could indicate a non-cubic lower symmetry, SEM-EDS and Rietveld powder refinement methods were used. The SEM-EDS results have shown that the garnet has a (Ca3.00Mn0.01)3.01(Al1.82Fe0.15Ti0.02)1.99(Si2.97Al0.03)3.00O12 chemical composition (i.e., Grs91Adr08), which can be more specifically explained as ferric iron containing grossular. The next step further used Rietveld powder refinements of the various crystal structures in the Ia‾3d, R‾3c, R‾3, I41/a, Fddd, C2/c, and I‾1 space groups as well as a single mixture, which was followed by a comparative analysis of the R-values, site occupancy factors, and bond lengths and angles. The synthesis of these results showed both that the studied grossular garnet is not cubic and that it crystallized in the disordered Fddd space group with the final RB = 5.29% and RF = 1.75%. It was presumed that the grossular formed at temperatures between 150 and ~600 °C. [ABSTRACT FROM AUTHOR]

The effect of elastic constants, cij, on the nature (easy or difficult) of a cleavage system in mono-crystalline YBa2Cu3O7−δ is investigated by employing a novel three-dimensional eigenfunction expansion technique, based in part on the separation of the thickness variable and partly on a modified Frobenius-type series expansion technique in conjunction with Eshelby–Stroh formalism. Out of the three available, complete sets of elastic constants, only the experimental measurements using resonant ultrasound spectroscopy merit serious attention, despite reported values of c12 and, to a lesser extent, c66 being excessively high. The present investigation considers six through-thickness crack systems weakening orthorhombic mono-crystalline Yttrium barium copper oxide (YBCO) plates. More importantly, the present investigation establishes sufficient conditions for crack path stability/instability, which entail a cleavage system being easy or difficult, i.e., whether a crack would propagate in its original plane/direction or deflect to a different one. This criterion of fracture mechanics is then employed for accurate determination of the full set of elastic constants of superconducting mono-crystalline YBCO. Finally, heretofore unavailable results pertaining to the through-thickness variations of stress intensity factors and energy release rates for a crack corresponding to symmetric and skew-symmetric hyperbolic cosine loads, which also satisfy the boundary conditions on the plate surfaces, bridge a longstanding gap. [ABSTRACT FROM AUTHOR]

In this paper, detailed studies of structural, micro-structural, dielectric, electrical and magneto-electric characteristics of chemically synthesized a new double perovskite, BiSrFeCeO6 (strontium cerate-modified bismuth ferrite), are reported. The basic crystal data (unit cell dimension and orthorhombic crystal system) of the compound were obtained by analysing the room temperature X-ray powder diffraction data. Study of the surface microstructure of a sintered pellet sample, recorded by scanning electron microscope at room temperature, reveals the formation of high-density sample with the homogeneously and uniformly distributed grains of different size and shape. Analysis of frequency-temperature dependence of dielectric parameters and nature of hysteresis loop has exhibited the ferroelectric characteristics of the material. Studies of complex impedance and modulus components at different temperatures and frequencies have provided electrical characteristics of grains and grain boundaries present in the material, which are closely related to its microstructure. Thus, the correlation between the crystal structure with electrical properties and relaxation mechanism of the prepared sample has been established. The type of dielectric relaxation process and mechanism occurred in the compound have also been studied not only by analysis of the dielectric properties (εr, tan δ) and impedance parameters, but also from the study of frequency-temperature conductivity. The existence of negative temperature coefficient of resistance (NTCR) characteristics in the material has been confirmed from the temperature and dc conductivity analysis. Similarly, the frequency and ac conductivity analysis show that the studied compound follows Jonscher's universal power law. Based on the structural, ferroelectric, magnetic and magneto-electric characteristics, multiferroism in the new composition of bismuth ferrite has been established. [ABSTRACT FROM AUTHOR]

1,3,5-Triazine derivatives have a wide range of biological and pharmaceutical activities. According to the extensive application of this compounds, 3-(4-chloro-6-(4-morpholinophenyl)amino)-1,3,5-triazin-2-yl)amino)-N-methylthiophene-2-formamide was synthesized and characterized by 1H-NMR, 13C-NMR, HRMS, FT-IR, and single crystal X-ray diffraction. Moreover, density functional theory (DFT) calculations of this compound were carried out at B3LYP/6-311 level. The result indicated that the crystal structure was orthorhombic crystal system. Moreover, the biological activity of this compound was evaluated as novel FAK inhibitor. [ABSTRACT FROM AUTHOR]

In this paper, nonlinear optical (NLO) active single-crystal 2-amino-6-ethoxy benzothiazolium diphenylacetate (BTDPA) crystallized in an orthorhombic crystal system with non-centrosymmetric space group P212121. The thermal studies (TG–DTA and DSC) and characterization studies such as FT-IR, FT-Raman, NMR, UV–Vis–NIR, PXRD, and NLO studies (Kurtz–Perry powder method) of BTDPA crystal were recorded and investigated. Molecular geometry of BTDPA was optimized using quantum chemical computational method with M06-2X functional and 6-31G** basis set. Frontier molecular orbitals, molecular electrostatic potential, and density of states were calculated for optimized geometry to see the trend of electronic charge distributions at ground state. The TD-M06-2X method was used to calculate electronic transitions which were compared with experimental UV–Visible spectrum of BTDPA. Additionally, at molecular-level static isotropic, anisotropic linear polarizability, and third-order NLO polarizability were also calculated which were found to be 42.33 × 10–24 esu, 24.27 × 10–24 esu, and 18.95 × 10–36 esu, respectively. The current investigation of BTDPA molecule highlights good optical and nonlinear optical properties which can be of added value in the field of optoelectronic and laser applications. [ABSTRACT FROM AUTHOR]

Bio-compatible water-soluble conjugates of Co(II), Cu(II) and Zn(II) (1–3), [Co(Boc- L -valine)2(imidazole)2], [Cu(Boc- L -valine)2(imidazole)2], and [Zn(Boc- L -valine)2(imidazole)2], were synthesized and comprehensively characterized by various spectroscopic techniques (UV–visible, FT-IR, ESI-MS, EPR, 1H NMR, 13C NMR) and single crystal X-ray diffraction which showed that the complexes 1–3 crystallized in an orthorhombic crystal system, in a slightly distorted octahedral geometry having the space group P21212. Density functional theory calculations were performed to correlate the energy of frontier molecular orbitals with the stability and reactivity of the complexes. In vitro DNA binding interaction studies of complexes were performed by employing various biophysical techniques and their corroborative results revealed (i) the electrostatic mode of binding in the groove region of DNA, (ii) pBR322 plasmid cleavage at a low concentration of 5–12.5 μM via an oxidative pathway in complexes 1 and 2 and the hydrolytic mechanism in the case of 3, (iii) changes in the 1H NMR chemical shift values of the NH2 group of GMP after interaction with complex 3, (iv) alteration in the EPR parameters of complex 2 after complexation with DNA, (v) SOD mimetic activity of complex 2 with the IC50 value of 2.08 μM and (vi) a good and selective cytotoxicity profile against chemo-resistant MCF-7 and MDA–MB–231 cancer cell lines by complex 1. Molecular docking studies complemented the spectroscopic results and confirmed the electrostatic interaction of complexes in the groove region of DNA. [ABSTRACT FROM AUTHOR]

In this research, AgNbO3 ceramics were produced by two sintering methods: reaction sintering (RS) and conventional solid-state sintering (CSSS). The process was similar for both methods, except that in RS, Ag2O and Nb2O5 precursors were mixed, then formed into pellets, skipping the calcination step, and sintered at 1100 °C for 6 hours. Both prepared ceramics had the same perovskite crystal structure with an orthorhombic crystal system and Pbcm and Pmc21 space groups with similar lattice dynamic vibration modes at room temperature. The average grain size of the polycrystalline samples prepared by RS and CSSS was found to be ∼2.03 ± 0.77 and ∼1.85 ± 0.96 μm, respectively. The relative bulk densities of the ceramics produced by RS and CSSS were found to be ∼94.0 ± 1.8 and ∼96.5 ± 1.3%, respectively. Ceramics prepared by both methods showed antiferroelectric behavior, and reaction-sintered AgNbO3 ceramics exhibited lower energy loss density than CSSS samples. In addition, a recoverable energy storage density (Wrec) of 3.1 J cm−3 and higher energy storage efficiency (η) for RS samples were measured at 175 kV cm−1. Moreover, the η values of 74.2% and 57.7% were measured for samples sintered by RS and CSSS, respectively. This energy storage efficiency is the highest ever reported for pure AgNbO3 ceramics. Furthermore, reaction-sintered samples showed good temperature stability for Wrec and η in the 30–80 °C temperature range. [ABSTRACT FROM AUTHOR]

Single crystals of pure and Cdcl2 added sodium penta fluro antimonates, an electro optical crystal has been grown by slow evaporation technique. The grown crystals are subjected to single crystal X-ray diffraction, Fourier Transform Infrared(FTIR) studies, EDAX, UV-Vis studies and microhardness studies. Single crystal X-ray diffraction confirms that the crystal belongs to Orthorhombic system. The FTIR spectrum analysis has confirmed the functional groups in the grown crystal. The optical behaviour was examined by UV-Vis studies and found that the crystal is transparent in the entire visible region. Microhardness studies reveals the mechanical strength of the grown Crystal. The decomposition point of the sample was identified by TG/DTA studies. The samples was measured and Dielectric properties were measured at different frequencies and temperature. [ABSTRACT FROM AUTHOR]

We report the synthesis of single crystals of the quaternary sulfide, BaCeCuS3, for the first time by heating a polycrystalline sample of BaCeCuS3 with an excess of KCl flux inside a vacuum-sealed fused silica tube. The crystal structure of the compound is determined by a single-crystal X-ray diffraction study which shows that it crystallizes in the primitive orthorhombic crystal system (space group: Pnma) with cell constants of a = 10.6740(13) Å, b = 4.1200(6) Å, and c = 13.409(2) Å. The structure is best described as a pseudo-two-dimensional structure where tetrahedral CuS4 and octahedral CeS6 units serve as the main building blocks. The polyanionic layers in the structure are separated by the presence of electropositive Ba2+ cations. The optical absorption study on the polycrystalline sample of BaCeCuS3 shows a semiconducting nature with a direct bandgap of 1.8(2) eV consistent with the green color of the sample. The temperature-dependent thermal conductivity (ktot) measurements on the polycrystalline BaCeCuS3 sample reveal an extremely low value of ktot (0.32 W m−1 K−1) at 773 K. DFT calculations were carried out to obtain the electronic structure of the title compound. Our theoretical studies predict a high value of the thermoelectric figure of merit (>1) for BaCeCuS3 by optimization of the charge carriers. To also explore a practical application of BaCeCuS3, a liquid junction solar cell was fabricated: TiO2/CdS/BaCeCuS3/Sn2−/S2−/MWCNTs@Ni, and the cell delivered an efficiency enhanced by ∼45% compared to the one without the sulfide. The performance improvement is affected by the hole conducting properties of BaCeCuS3, which allows facile hole transfer from CdS to the polysulfide, increases the charge separation, and hence increases the efficiency. [ABSTRACT FROM AUTHOR]

We report the synthesis of single crystals of the quaternary sulfide, BaCeCuS3, for the first time by heating a polycrystalline sample of BaCeCuS3 with an excess of KCl flux inside a vacuum-sealed fused silica tube. The crystal structure of the compound is determined by a single-crystal X-ray diffraction study which shows that it crystallizes in the primitive orthorhombic crystal system (space group: Pnma) with cell constants of a = 10.6740(13) Å, b = 4.1200(6) Å, and c = 13.409(2) Å. The structure is best described as a pseudo-two-dimensional structure where tetrahedral CuS4 and octahedral CeS6 units serve as the main building blocks. The polyanionic layers in the structure are separated by the presence of electropositive Ba2+ cations. The optical absorption study on the polycrystalline sample of BaCeCuS3 shows a semiconducting nature with a direct bandgap of 1.8(2) eV consistent with the green color of the sample. The temperature-dependent thermal conductivity (ktot) measurements on the polycrystalline BaCeCuS3 sample reveal an extremely low value of ktot (0.32 W m−1 K−1) at 773 K. DFT calculations were carried out to obtain the electronic structure of the title compound. Our theoretical studies predict a high value of the thermoelectric figure of merit (>1) for BaCeCuS3 by optimization of the charge carriers. To also explore a practical application of BaCeCuS3, a liquid junction solar cell was fabricated: TiO2/CdS/BaCeCuS3/Sn2−/S2−/MWCNTs@Ni, and the cell delivered an efficiency enhanced by ∼45% compared to the one without the sulfide. The performance improvement is affected by the hole conducting properties of BaCeCuS3, which allows facile hole transfer from CdS to the polysulfide, increases the charge separation, and hence increases the efficiency. [ABSTRACT FROM AUTHOR]

Photodynamic antimicrobial therapy (PDAT) is a new method for the treatment of microbial infections. However, there have been few reports on the photodynamic antimicrobial activity of corrole, which has a significant advantage in the treatment of photodynamic antitumor activity. In this study, mono-hydroxyl corrole named 10-(4-hydroxyphenyl)-5,15-bis (pentafluorophenyl) corrole (P-OH) was synthesized. What' s more, its crystal structure and photodynamic antibacterial activity were also explored. The results indicate that mono-hydroxyl corrole belongs to orthorhombic crystal system and shows good photodynamic antibacterial activity. When the concentration of the drug is more than 2MIC, the bacteriostatic effect is showed. Whereas, the concentration of drug less than 2MIC shows antibacterial effect. The minimum bactericidal concentration and minimum inhibitory concentration of the drug are lower than porphyrin, it is a good photodynamic antibacterial photosensitizer. [ABSTRACT FROM AUTHOR]

EuScCuSe3 was synthesized from the elements for the first time by the method of cesium-iodide flux. The crystal belongs to the orthorhombic system (Cmcm) with the unit cell parameters a = 3.9883(3) Å, b = 13.2776(9) Å, c = 10.1728(7) Å, V = 538.70(7) Å3. Density functional (DFT) methods were used to study the crystal structure stability of EuScCuSe3 in the experimentally obtained Cmcm and the previously proposed Pnma space groups. It was shown that analysis of elastic properties as Raman and infrared spectroscopy are powerless for this particular task. The instability of EuScCuSe3 in space group Pnma space group is shown on the basis of phonon dispersion curve simulation. The EuScCuSe3 can be assigned to indirect wide-band gap semiconductors. It exhibits the properties of a soft ferromagnet at temperatures below 2 K. [ABSTRACT FROM AUTHOR]

The Ba 3 Y 2– x Er x (BO 3) 4 (х = 0.01, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3) phosphors were obtained by crystallization from a melt. The Ba 3 Y 2 (BO 3) 4 crystal structure was refined from single crystal X-ray diffraction data to R = 0.037. Its anisotropic atomic displacement parameters for all atoms were refined for the first time. The borate crystallizes in the orthorhombic crystal system, space group Pnma with unit cell parameters a = 7.673(1), b = 16.44(1), c = 8.977(2) Å, V = 1132.3(3) Å3, Z = 4. These phosphors are isotypical to those of the A 3 M 2 (BO 3) 4 (A = Ca, Sr, Ba, M = Ln , Y, Bi) family. The crystal structure contains the isolated BO 3 triangles, two general and a special one independent crystallographic sites for large cations, which are disordered over sites. Thermal behavior of Ba 3 Y 2 (BO 3) 4 was investigated by high-temperature X-ray powder diffraction and thermal expansion coefficients are calculated in a wide temperature range. An inflections of temperature dependencies of the unit cell parameters is observed in a range 600–740 °C. Luminescence spectra, excitation and kinetic curves of the Ba 3 Y 2 (BO 3) 4 :Er3+ series are reported. A maximum luminescence intensity is observed for the x = 0.1 sample. According to vibrational spectroscopy data no structural changes upon activation of the Ba 3 Y 2 (BO 3) 4 matrix with the Er ions are observed. • Novel Ba 3 Y 2 (BO 3) 4 :Er3+ phosphors are prepared and characterized. • Thermal behavior of Ba 3 Y 2 (BO 3) 4 is investigated over wide range of temperatures. • The optimum doping concentration of Ba 3 Y 2 (BO 3) 4 :Er3+ was determined to be 5 at.%. • Discussion on expansion of A 3 M 2 (BO 3) 4 (A = Ca, Sr, Ba, M = Ln , Y, Bi) borates is given. [ABSTRACT FROM AUTHOR]

Crystals of two new tetrafluoroborate crystallohydrates M(BF4)2·3H2O (M = Sr, Ba) are prepared by the evaporation of aqueous solutions. The compounds are studied by single crystal XRD and IR spectroscopy. Sr(BF4)2·3H2O crystallizes in the tetragonal crystal system (a = 6.9638(4) Å, c = 18.1671(12) Å, space group P42/mnm); Ba(BF4)2·3H2O crystallizes in the orthorhombic crystal system (a = 7.1996(2) Å, b = 18.0823(5) Å, c = 7.1860(2) Å, space group C2221). Their crystal structure is formed by isolated BF4 tetrahedra and water molecules with alkaline earth metal atoms in between. When cooled to 100 K, Ba(BF4)2·3H2O undergoes a polymorphic transition to the monoclinic modification accompanied by pseudo-merohedral twinning of crystals. [ABSTRACT FROM AUTHOR]

All-inorganic metal halides have shown significant applications in solid-state optoelectronics because of their flexible structures and impressive fluorescence emissions. In this study, a heterovalent cation substitution strategy was used to partially replace the divalent cadmium ions in CsCdCl3 with trivalent antimony ions to promote the production of self-trapped excitons, resulting in a bright broadband green photoluminescence of CsCdCl3∶ Sb3+ with a central wavelength of 530 nm. Mechanism researches results show that the adjacent SbCl6 octahedra in CsCdCl3∶ Sb3+ are isolated, forming a low-dimensional electronic configuration that promotes Sb3+ localization and achieves efficient photoluminescence with a quantum efficiency of up to 95. 5% . Furthermore, although both CsCdCl3 and RbCdCl3 belong to ACdCl3 ( A is an alkali metal family), they have distinctly different crystal structures. RbCdCl3 crystallizes in the orthorhombic crystal system with space group of Pnma; while CsCdCl3 crystallizes in the hexagonal phase crystal system with space group of P63/ mmc. The structural symmetry of CsCdCl3 is higher than that of RbCdCl3, indicating that its crystal structure is less distorted away from the cubic phase than that of RbCdCl3, resulting in a smaller Stokes shift and corresponding blue shift of the emission spectrum in CsCdCl3∶ Sb3+ than in RbCdCl3∶ Sb3+. This work not only provides a method for designing new photoluminescence materials by heterovalent cation substitution but also paves an avenue for modulating the luminescent properties of metal halides through crystal structure symmetry. [ABSTRACT FROM AUTHOR]

We report a new series of isatin-oxime-based Schiff base derivatives (p–H, p–Cl, p–CH3). Structural analyses of the compounds were conducted through FTIR, 1H NMR, UV–Vis, and elemental analyses. X-ray crystallography demonstrated that compounds 1 and 2 adopted an orthorhombic crystal system with a P bca space group. Hirshfeld surface (HS) analysis indicated that hydrogen bonding and van der Waals interactions were predominant in the crystal packing. The volumes of the crystal voids and the percentages of free spaces in the unit cells were calculated as 293.87 Å3 and 10.63% (for 1), 320.34 Å3 and 11.04% (for 2), respectively. The evaluations of energy frameworks showed that stabilization was dominated by electrostatic energy contributions in compounds. In silico investigations on the DNA binding activity showed that the binding activity of the compounds was mediated via intercalation. The anticancer activity of the compounds was also tested via an MTT assay using HepG2 (liver cancer), Caco-2 (colorectal adenocarcinoma), A549 (lung cancer) and HEK-293 (normal cell) cell lines. The MTT assay demonstrated significant cytotoxic activity of compound 1 across HepG2, Caco-2, A549, and HEK-293 cell lines, with IC50 values of 5.07 µM, 5.19 µM, 4.01 µM, and 5.63 µM, respectively, after 24 h, surpassing cisplatin in efficacy at all tested time intervals. The data indicate that substituents play a significant role in modulating cytotoxicity, with compound 1 (p–H) demonstrating the highest activity. These findings demonstrate the high cytotoxicity and cancer cell selectivity of isatin-oxime-based Schiff base derivatives, especially compound 1, suggesting their potential as strong alternatives to traditional chemotherapy agents. [ABSTRACT FROM AUTHOR]

Nanostructured copper oxide thin films were grown by the chemical spray pyrolysis (CSP) technique. Utilizing a homemade spray pyrolysis method, thin films are created. This work investigates the role of gamma ray and ultraviolet ray irradiation on the optical properties of copper oxide thin films(CuO) prepared. In this framework, used different substrate temperatures 300 °C, 350 °C, and 400 °C for the layers were grown on glass for the prepared CuO thin films. UV–visible spectrometer, field emission scanning electron microscopy (FE-SEM) and X-ray diffraction patterns(XRD) measurements were all used to characterize the samples. The UV–visible spectroscopy showed a decrease in the absorbance and the optical band gap of CuO thin films with the increase in the higher substrate temperatures before irradiation. Additionally, surface plasmon resonance peaks (λ SPR) were observed at 329 nm. FE-SEM images revealed spherical-like shapes with an average diameter range of 48 nm,56 nm and 62 nm for 300 °C, 350 °C, and 400 °C, respectively. An analysis of X-rays revealed that CuO thin films contained the crystallographic planes of a monoclinic and an orthorhombic crystal system. Also, when samples were exposed to gamma and UVC radiation, the absorbance intensity of CuO thin films increased, but the optical band gap decreased. • CuONPs films were exposed to γ-radiation source ranging from 0 to 10 kGy. • UV and gamma radiation increased the absorption of CuO NPs. • After irradiating with gamma and ultraviolet rays the optical energy gap is a decrease in the values of for all samples exposed. • Enhanced properties of CuO after irradiation make it suitable for use in photovoltaic devices and optoelectronic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Solution growth approach was used to grow a DLFTH single crystal. • DLFTH crystals shows orthorhombic crystal system with centrosymmetric space group of Pbcn. • The crystal possesses suitable mechanical strength for device fabrication. • Physicochemical properties of DLFTH suggest its suitability for the NLO applications. In this work reports on the growth and characterization of semiorganic NLO single crystal of DiLithium Fumarate TetraHydrate (DLFTH) using a slow evaporation technique. The crystal structure was an orthorhombic crystal system with the centrosymmetric space group Pbcn, as demonstrated by single crystal X-ray diffraction (SCXRD) investigations. The UV–Vis-NIR spectrum is used to derive optical parameters, such as the lower cut off wavelength (277 nm) and optical energy band gap Eg = 4.98 eV. DLFTH crystals belongs to hard material category using Vickers microhardness test. From NLO studies, the nonlinear optical parameters were studied, such as the nonlinear refractive index (n 2), absorption coefficient (β) and third order NLO susceptibility (χ3). The crystal has the properties of saturable absorption and self-defocusing nature. Third order NLO susceptibility (χ3) were found to be 4.14384 × 10-10 esu. The higher χ3 number is due to the presence of hydrogen bonds between C-H-O and O-H-O atoms. Therefore, we confirm that it's applicability for optical device applications. [ABSTRACT FROM AUTHOR]

• A convenient and facile synthesis of carbazate based imines (a and b) were accomplished by refluxing t‑butyl/ethyl carbazate with furaldehyde in ethanol. • The presence of pi...pi and CH...Pi stacking interactions are distinguishing characteristic of crystal packing in both target compounds. • Hirshfeld surface analysis was also applied to discern the intermolecular interactions. • A theoretical foundation for the logical design of new carbazate compounds as substrate inhibitors for Harmone-sensitive lipases is provided by the docking data. A convenient and facile synthesis of tert‑butyl (E)-2-(furan-2-ylmethylene) hydrazine-1-carboxylate (a) and ethyl (E)-2-(furan-2-ylmethylene) hydrazine-1-carboxylate (b) were accomplished by refluxing t‑butyl/ethyl carbazate with a furaldehyde in solvent ethanol. The interactions between and within two synthesised imine compounds were characterised and identified by the utilisation of spectroscopic techniques in conjunction with X-ray crystallography and theoretical computations. Compound a crystallises in orthorhombic crystal system with Pbca space group, while as compound b crystalizes in monoclinic crystal systems with space groups Cc. The presence of CH...π stacking and π...π stacking interactions are distinguishing characteristic of crystal packing in both target compounds. Their solid-state behaviour was also studied using Hirshfeld surfaces. Crystal packing motifs were investigated with the aid of Hirshfeld surface fingerprint plots. Furthermore, investigations related to calculations of the molecular electrostatic potential and frontier molecular orbital (highest occupied-lowest unoccupied) were carried out for the optimised structure. Finally, Hormone-sensitive lipase (HSL) (PDB-ID 6KEU) protein was used to conduct molecular docking investigations of compound a and b. [Display omitted] [ABSTRACT FROM AUTHOR]

• LVIA single crystals were grown by slow evaporation method. • The optical direct bandgap energy was found to be 5.43 eV. • The SHG efficiency of crystal was 0.89 times that of KDP. A nonlinear optical single crystal of L-Valine Itaconic Acid (LVIA) was grown at room temperature from an aqueous solution by using the slow evaporation method. The grown crystal was undergone X-ray diffraction investigation, which confirm that the crystal belongs to orthorhombic system with the non-centro symmetric P bca space group. This single crystal contains several functional groups, according to FTIR spectroscopic analysis there were identified. By analyzing the crystal's UV–visible spectrum, based on its optical transparency this crystal may use for optoelectronic device manufacturing. The emission happens at 553 nm wavelength, according to the photoluminescence spectrum. Thermo gravimetric and differential thermal analytical studies helps us to measure title crystal melting point and thermal stability. At various temperatures, the dielectric property of the crystal was found out. The Kurtz-powder method has been used to study the phenomenon of Second Harmonic Generation (SHG) in the crystal. [ABSTRACT FROM AUTHOR]

Pure and Cr doped L-asparagine monohydrate (LAM) single crystals were grown by evaporation controlled solution growth technique. SCXRD, Hirshfeld surface and fingerprint plot were performed for grown crystals. High transmittance, increase in optical bandgap and hardness were observed as result of Cr doping. Therefore, Cr doping makes LAM a better candidate for device fabrication and optoelectonics applications. [Display omitted] • Effect of Cr doping in LAM crystal grown by solution method was investigated. • High transmittance and lower cutoff wavelength were observed in UV–Vis analysis. • Intermolecular interactions were investigated by Hirshfeld surface analysis. • Cr doping has changed the 'soft' nature of crystal to 'hard' nature. • Pits were created on smooth surface of pure crystal due to Cr addition. Pure and chromium (Cr) doped L-asparagine monohydrate (LAM) single crystals were grown by using evaporation controlled solution growth technique. XRD analysis confirmed the orthorhombic crystal system with space group P2 1 2 1 2 1 of grown crystals. Cr-incorporation decreased the cell parameters and unit cell volume of the crystals. Intermolecular interactions were analysed through Hirshfeld and fingerprint studies. SEM analysis showed the appearance of pits on the smooth surface of pure crystal due to Cr-addition. UV–Vis analysis showed high transparency, low cut-off and direct band gap of 5.42 eV and 5.51 eV for pure and Cr doped crystals, respectively. Fundamental functional groups were identified by FTIR and Raman spectroscopy. The thermal stability and melting point of the crystals were investigated using TGA/DSC analysis. The dielectric constant for doped LAM was increased to 44 as compare to dielectric constant of pure crystal which was 32. Both crystals showed low dielectric loss, having values 0.04 and 0.006 for pure LAM and doped crystals, respectively. In Vickers microhardness test, Cr doping was found to change the nature of pure LAM crystal from 'soft' to 'hard' as Meyer's index changed from 2.48 to 1.24. [ABSTRACT FROM AUTHOR]

[Display omitted] • SSY dye makes a different pattern in ZTS crystal from the other reported dye-doped single crystals. • The optical bandgap and other optical constants are enhanced in SSY-dyed ZTS crystals. • The coefficient d 33 of piezoelectricity is enhanced in the dyed ZTS single crystal. • The mechanical strength of ZTS crystal has improved after the inclusion of SSY dye molecules. • SSY dye improves the dielectric nature of ZTS crystal. Organic dye can induce positive changes in optical, mechanical and electrical properties of semi-organic single crystals. Single crystals of pure and 0.01 mol% SSY dye doped ZTS are grown from a slow evaporation solution technique. The structural properties of pure and SSY-dyed ZTS crystals are characterized using SCXRD and PXRD, confirming the maintenance of crystallinity and incorporation of dye molecules within the host lattice of ZTS crystal. Both ZTS crystals belong to orthorhombic crystal system with space group Pca2 1. The refined lattice parameters and cell volume of present pure ZTS crystal are a = 11.1723 Å, b = 7.7989 Å, c = 15.5357 Å, α = β = γ = 90°, V = 1353.6762 Å3. The intensity of all Raman peaks in ZTS is enhanced by the incorporation of dye. Optical spectroscopic UV–visible and photoluminescence techniques highlight the comparative studies of light absorption, energy bandgap, optical constants and fluorescence emission. An increment of 0.05 eV in optical bandgap is observed in dyed ZTS. The dielectric properties with variation in frequency range (23 Hz–10 MHz) at different temperature range (30–100 °C) are evaluated through impedance spectroscopy, showing an increase in dielectric constant around 15 % and reduction in dielectric loss, indicating potential for improved performance in electronic applications. A significant enhancement is observed in the piezoelectric coefficient (d 33) in dyed ZTS single crystals. The d 33 value of ZTS is increased from 2.75 to 2.95 pC/N by the doping of organic dye. Vickers micro-hardness tester is used to know the mechanical strength through micro-indentation, which illustrated an increase in the hardness nature of dyed ZTS single crystals. These findings provide a foundation for the future development of ZTS-based materials for technological applications, offering a promising route for the advancement of functional materials in the domain of piezoelectric and optoelectronic technologies. [ABSTRACT FROM AUTHOR]

Under solvothermal synthetic condition, lactate derivatives (R)-5-(1- carboxyethoxy)isophthalic acid ((R)-H 3 CIA) and (S)-5-(1-carboxyethoxy)isophthalic acid ((S)–H 3 CIA) assembled with Ca(Ⅱ) and Mn(Ⅱ) ions to obtain enantiomers {[MnCa 0.5 ((R)-CIA)(H 2 O)]·((CH 3) 2 NH 2 CH 3 CO 2) 0.5 (H 2 O)} n (HU21- R ) and {[MnCa 0.5 ((S)-CIA)(H 2 O)]·((CH 3) 2 NH 2 CH 3 CO 2) 0.5 (H 2 O)} n (HU21– S ), respectively. Complexes HU21- R and HU21– S belong to orthorhombic crystal system with chiral space group I 2 1 2 1 2 1. Single crystal X-ray diffraction analysis revealed that all oxygen atoms of synthons (R)-CIA3- and (S)-CIA3- participated in the coordination with metal ions. Thus, semi-rigid (R)-CIA3- and (S)-CIA3- anions become rigid linkers in HU21- R and HU21– S . Fragments of (R)-CIA3- anion are connected by Ca(Ⅱ) ions to build right-handed double helical chains in HU21- R , while the enantiomeric left-handed double helixes are constructed by (S)-CIA3- fragments and Ca(Ⅱ) ions in HU21– S . Additionally, Mn(Ⅱ) centers and CIA3− anions resulted in a rare 4,4,4-connected net with point symbol of (42.62.82) 3 (42.64). Ca(Ⅱ) ions were further filed into Mn-CIA-framework to form a three dimensional structure with one dimensional channel. Moreover, magnetic test indicates that the framework has a canted antiferromagnetic behavior. Enantiomeric lactate derivatives as rigid synthons assembled with Ca(Ⅱ) and Mn(Ⅱ) ions to result in three dimensional helical heterometallic frameworks with one dimensional channels. [Display omitted] • Chiral heterometallic framework. • Double helical chain. • Lactate derivative as rigid synthon. [ABSTRACT FROM AUTHOR]

Two novel lanthanide based two-dimensional metal–organic framework (MOF) compounds [Tb(NDC)(NO 3)(DMA) 2 ] n (MOF- 1) and [Ho(NDC)(NO 3)(DMA) 2 ] n (MOF- 2) [H 2 NDC= 2,6-naphthalenedicarboxylic acid and DMA = N, N -dimethylacetamide] have been synthesized through solvothermal route and structurally characterized. MOFs feature a "paddle-wheel" (PW) type core building units which are constructed via carboxylato oxygen coordinated to lanthanide atoms. Paddle-wheel cores are interconnected to each other to give rise to layered network structure in both the cases. 2D lanthanide based MOFs consist of paddle-wheel building block are rare in the literature. Notably, both MOF- 1 and MOF- 2 are capable to catalyze O-arylation reaction efficiently under heterogeneous medium. [Display omitted] Two novel lanthanide based two-dimensional metal-organic framework (MOF) compounds [ Tb (NDC)(NO 3)(DMA) 2 ] n (MOF- 1) and [Ho(NDC)(NO 3)(DMA) 2 ] n (MOF- 2) [H 2 NDC=2,6-naphthalenedicarboxylic acid and DMA=N, N -dimethylacetamide] have been synthesized following solvothermal route and structurally characterized. Structural analysis reveals that both the compounds are crystallized in the orthorhombic crystal system with space group Pbca. MOFs feature a "paddle-wheel" (PW) type core building units which are constructed via carboxylato oxygen coordination with lanthanide atoms. 2D lanthanide based MOFs consist of paddle-wheel building block are rare in the literature. MOF- 1 and MOF- 2 possess an octa-coordinated metal center. Apart from carboxylato groups, oxygen atoms of DMA and NO 3 − ions are also coordinated to metal centers. Paddle-wheel cores are interconnected to each other to give rise to layered network structure in both the cases. 2D layers are propagated parallel to bc plane and layers are stacked one upon another along the crystallographic a axis. Notably, both MOF- 1 and MOF- 2 are capable to catalyze O-arylation reaction efficiently under heterogeneous medium. However, amongst them, catalytic efficacy of MOF- 1 towards O-arylation reaction is found to be better than that of MOF- 2. [ABSTRACT FROM AUTHOR]

The organic aromatic 4-methoxy-2-nitroaniline single crystal was grown by the slow evaporation method. The single crystal X-ray diffraction (XRD) and powder XRD analyses show that the grown crystal belongs to an orthorhombic crystal system and the obtained unit cell parameters are a = 16.17 Å, b = 6.55 Å, c = 7.14 Å, α = 90°, β = 90°, and γ = 90°. The various functional groups present in the grown crystal were identified by using Fourier transform infrared (FTIR) and FT-Raman spectral analyses. The optical properties of the grown single crystal were analyzed by UV–Vis-NIR studies, and the optical parameters are calculated. The photoluminescence analysis reveals that the high-intensity emission peak was observed around 599 nm. The thermal (TG/DTA) analyses were used to investigate the melting and decomposition points of the grown 4-methoxy-2-nitroaniline single crystal. The Coats-Redfern and Horowitz-Metzger methods were used to calculate the kinetic and thermodynamic parameters like the activation energy (E), frequency factor (Z), enthalpy (ΔH*), entropy (ΔS*), and Gibbs free energy (ΔG*). The Agilent LCR meter was used to analyze dielectric properties at various temperatures ranging from 40 to 120 °C and frequencies ranging from 100 Hz to 1 MHz. The nonlinear optical properties of 4-methoxy-2-nitroaniline were measured using the Z-scan technique, with 532 nm diode pumped continuous wave (CW) Nd:YAG laser. [ABSTRACT FROM AUTHOR]

The aim of this study was to synthesize and examine the molecular docking of a Mo(VI) complex [Mo(dien)O3] (1), {N1-[2-(amino)ethyl]ethane-1,2-diamine}-[tris(oxido)]-molybdenum(VI) as a potential antivirus drug against the SARS-CoV-2, HIV and polio viruses. [Mo(dien)O3] (1) was fully characterized, including single crystal x-ray crystallography. The complex was crystallized in the orthorhombic crystal system with Pbcm space group and has distorted octahedral coordination geometry. DFT calculations have been explored for structure-property relationships. The Hirshfeld surface analysis and 2D fingerprint plots were also performed to investigate intermolecular interactions in the crystal structure. Antibacterial activities of 1 were also studied. In order to have insight into the potential application of 1 as an effective antivirus agent, we have examined the molecular docking of 1 with SARS-CoV-2 Mpro (PDB ID: 7N0I), HIV virus (PDB ID: 6MCF) , Polio virus (PDB ID: 1HXS), and DNA duplex dodecamer (PDB ID: 1BNA). The molecular docking results reveal that 1 with Mpro of SARS-CoV-2, HIV-1 RNA and Polio virus resulted in binding energies (ΔG) of −9.9 kcal/mol, −8.8 kcal/mol and −8.4 kcal/mol with good inhibition constant (Ki) of 6.539 µM, 5.113 µM and 4.237 µM, respectively. Overall, in silico molecular docking predicts potential antivirus effects of 1 against the virus of SARS CoV-2, HIV, and Polio. [ABSTRACT FROM AUTHOR]

A phase field model for cubic to orthorhombic martensitic transformation (MT) at the nanoscale in a β titanium (Ti) alloy Ti-24Nb-4Zr-8Sn (in wt.%) is investigated by finite element simulation. The approach is based on phase field theory, time-dependent Ginzburg-Landau theory, and mechanical equilibrium equations. Partial differential equations (PDEs) were solved using the commercial software COMSOL Multiphysics. The morphology of the product phase exhibits plate-like or needle-like shapes that reduce the elastic strain energy of the system. The simulation result for random initial order parameters is in agreement with previous experimental observations. The final volume fractions of two different orthorhombic martensitic variants are not dependent on the initial conditions. [ABSTRACT FROM AUTHOR]

The applicability of an atomistic Class II force field to capture the properties of the orthorhombic crystal phase of ammonium perchlorate was investigated. Structural and dynamical behaviors including density, lattice parameters, bulk modulus, infrared spectrum, and rotational dynamics were calculated from the trajectories of molecular dynamics (MD) simulations. Properties calculated from MD were compared to available experimental data over a range of temperatures, including those significantly higher than the parameterization temperature of 10 K. [ABSTRACT FROM AUTHOR]

By means of ab initio computations and the global minimum structure search method, we have investigated structural, mechanical, and electronic properties of D-carbon, a crystalline orthorhombic sp³ carbon allotrope (space group Pmma [D2h5] with 6 atoms per cell). Total-energy calculations demonstrate that D-carbon is energetically more favorable than the previously proposed T6 structure (with 6 atoms per cell) as well as many others. This novel phase is dynamically, mechanically, and thermally stable at zero pressure and more stable than graphite beyond 63.7 GPa. D-carbon is a semiconductor with a bandgap of 4.33 eV, less than diamond's gap (5.47 eV). The simulated X-ray diffraction pattern is in satisfactory agreement with previous experimental data in chimney or detonation soot, suggesting its possible presence in the specimen. Published by AIP Publishing. [ABSTRACT FROM AUTHOR]

Electron spin resonance (ESR) spectra of surface and interface recombination centers recently observed on (001) silicon wafers, labeled Pm and KU1, were studied using spin dependent microwave photoconductivity. Both ESR spectra, having the orthorhombic symmetry and spins S =1/2 and S =1 for Pm and KU1, respectively, were observed in the commercially available surface oxidized (001)-Si wafers. Systematic studies on annealing and oxidation conditions for the Pm and KU1 formation conclude that both ESR spectra arise from the same center that contains the interaction between the two nearest Si dangling bonds on the (001) Si surface. [ABSTRACT FROM AUTHOR]

A novel nonlinear optical (NLO) single crystal of L-histidine phthalic potassium iodide (LHPPI) with dimensions of 8 × 8 × 3 mm3 was obtained from aqueous solution by slow solvent evaporation method. Single-crystal X-ray diffraction (SCXRD) results showed that the grown LHPPI crystal belongs to the orthorhombic crystal system with noncentrosymmetric space group P212121. Powder X-ray diffraction (PXRD) spectrum, the hkl plane orientations show the phase identity of the LHPPI crystal. The elemental composition of the grown LHPPI crystal was confirmed by EDS analysis. The functional groups were identified by fourier transform infrared (FTIR) study. The optical quality of the LHPPI crystal was studied using UV–Vis DRS spectrum analysis. The chemical etching studies were carried out to estimate the dislocation density. Vicker's microhardness study revealed that the LHPPI crystal exhibits reverse indentation size effect (RISE) and belongs to soft category. The dielectric constant (εr) and dielectric loss (ε') as a function of frequency were measured. The thermal properties of the LHPPI crystal were investigated by TG/DTA studies. The second harmonic generation (SHG) efficiency of the LHPPI crystal was measured by Kurtz–perry powder method. Thus, the results suggest that the LHPPI single crystal is of particular interest for NLO device application. [ABSTRACT FROM AUTHOR]

In this work, orthorhombic (α-BiNbO4) and triclinic bismuth niobate (β-BiNbO4) ceramics were prepared by a wet chemical route. The structure of the obtained powders was characterised by X-ray diffraction and the morphology by scanning electron microscopy. The dielectric measurements were performed in the radiofrequency region, at different temperatures, using the impedance spectroscopy technique. The α-BiNbO4 sample presented a temperature-dependent relaxation process, with the corresponding activation energy being calculated through the Arrhenius equation. The AC conductivity dependence on the frequency was in agreement with Jonscher's universal power. The conduction mechanism in the α-BiNbO4 compound is governed by two processes, which can be ascribed to a hopping transport mechanism. The correlated barrier hopping model until 280 K and the non-overlapping small polaron tunnelling model above 280 K are the most suitable models to describe the conductivity of this sample. In the β-BiNbO4 compound, the motion of mobile charge carriers involves localised hopping between neighbouring sites. [ABSTRACT FROM AUTHOR]

A new luminescent lanthanide coordination polymer composed of europium(III), oxalate and carbonate was prepared. A hydrothermal synthesis technique was applied to an aqueous solution of europium(III) nitrate and oxalic acid (H2ox), resulting in a carbonate-fixed compound, [Eu2(ox)(CO3)2(H2O)2]n, which was characterized using elemental, spectroscopic, thermal and crystallographic analyses. The number of aqua ligands could be reduced in comparison with the known europium(III) oxalate pentahydrate. The present reaction can be regarded as a rare example, where CO2 was incorporated into a compound under acidic reaction conditions. An infinite layer comprises Eu3+ and carbonate ions parallel to the crystallographic ac plane, and ox anions bridge the layers as a pillar in the b direction, thus affording a three-dimensional polymer in an orthorhombic crystal system. The photophysical properties were studied based on the emission spectra. The emission quantum yield was found to be 10.6% (excited at 400 nm), despite the presence of water as a ligand. Antenna effects do not work in the present compound. The lifetimes were 0.40, 0.41, and 0.37 ms for the emissions at 590, 615, and 690 nm, respectively, which are longer than that of the known europium(III) oxalate pentahydrate. [ABSTRACT FROM AUTHOR]

Vanadium pentoxide (V2O5) and multiwalled carbon nanotubes added V2O5 composite (MWCNT/V2O5) films were prepared by hydrothermal technique. The influence of various levels of MWCNT on the electrochromic properties of MWCNT/V2O5 films was investigated. X-ray diffraction analysis revealed that the films are polycrystalline in nature and belong to orthorhombic crystal system of V2O5. Raman and FTIR spectral analyses confirmed the formation of V2O5 phase and the influence of MWCNT on the vibrational frequencies of V2O5 films. V2O5 film added with 1 wt.% MWCNT showed enhanced transmittance and the bandgap of V2O5 increases with further increase in the addition of MWCNT in V2O5 films. The electrochromic studies revealed electrochromic reversibility of 82% (1 wt.% MWCNT added film) and 82.5% (5 wt.% MWCNT added film) whereas after 100 cycles the films added with 1 wt.% and 5 wt.% of MWCNT acquired excellent electrochromic reversibility of 92% and 88%, respectively. Further the switching kinetics of the film added with 1 wt.% MWCNT is 1.8 s for coloration and 2.4 s for bleaching processes. [ABSTRACT FROM AUTHOR]

A mixed ligand containing a Cu(II) complex, CuM [Cu(L·bpy)(NO3)] {LH = 1-(2-hydroxyphenyl)-3-(3-methyl-2-thienyl)-2-propen-1-one, bpy = 2,2′-bipyridine}, has been synthesized and characterized using spectroscopy and X-ray crystallography. It forms an orthorhombic crystal system with space group, Pbca. The Cu(II) metal exhibits slight distortion in a square pyramidal geometry in which an oxygen atom from the nitrate occupies the central apex, and the N2O2 core from chalcone and bipyridine form the basal plane. The crystal structure shows C–H⋯O, C–H⋯S and π–π weak non-covalent interactions and forms a chair-like 2D supramolecular architecture which is further analysed through hirshfeld surfaces, fingerprint plots and energy frameworks. The natural bond orbital, time dependent DFT and polarizability calculations are evaluated using the B3LYP/6-31G++(d,p) basis set for C, H, N, and O, and LANL2DZ set for copper. The DFT calculated nonlinear optical (NLO) responsive properties i.e. dipole moment (μ), polarizability (α), first hyperpolarizability (β), and second hyperpolarizability (γ) have promising values in gas as well as solvent phases (methanol, acetonitrile, water, DSMO). The NLO properties i.e. first and second hyperpolarizability (β, γ) of CuM in the gas phase are calculated as 20.36 × 10−30 esu and 2775.176 × 10−36 esu, respectively. The computed NLO properties enhance with solvent polarity. The calculated nonlinear optical properties indicate that CuM is a strong candidate for the fabrication of future optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this report, the effect of rare-earth (RE3+) ion substitution on structural, microstructural, and electrical properties in barium bismuth titanate (BaBi4Ti4O15) (BBTO) Aurivillius ceramics has been investigated. The Rietveld refinements on X-ray diffraction (XRD) patterns confirm that all the samples have an orthorhombic crystal system with A21am space group. Meanwhile, temperature dependent synchrotron XRD patterns reveal that the existence of dual phase in higher temperature region. The randomly oriented plate-like grains are experimentally strived to confirm the distinctive feature of bismuth layered Aurivillius ceramics. The broad band dielectric spectroscopic investigation signifies a shifting of ferroelectric phase transition (Tm) towards low temperature region with a decrease of the RE3+-ionic radii in BBTO ceramics. The origin of diffuse ferroelectric phase transitions followed by stabilization of the relaxor ferroelectric nature at high frequency region is explained using suitable standard models. The temperature dependent ac and dc conductivity results indicate the presence of double ionized oxygen vacancies in BBTO ceramics, whereas the dominance of single ionized oxygen vacancies is observed in RE-substituted BBTO ceramics. The room temperature polarization vs. electric field (P–E) hysteresis loops are shown to be well-shaped symmetric for BBTO ceramics, whereas slim asymmetric ferroelectric characteristics developed at RE-substituted BBTO ceramics. [ABSTRACT FROM AUTHOR]

Synthesis and crystal structures of 1-benzoyl-4-(4-nitrophenyl)piperazine, C17H17N3O3, (I) and 1-(4-bromobenzoyl)-4-phenylpiperazine, C17H17BrN2O, (II) are described. Compounds I and II crystallize in the orthorhombic and monoclinic crystal systems with space groups Pna21 (Z = 2, I) and P21 (Z = 1, II), respectively. The crystal of II was a two-component aggregate, treated as a 'twin' for data-acquisition purposes. There are no conventional hydrogen bonds in either I or II, but there are weaker C--H--O contacts. Each molecule consists of a central piperazine ring in a chair conformation, with either benzoyl and nitrophenyl (I) or 4-bromobenzoyl and phenyl (II) groups attached to different nitrogen atoms of the piperazine. The various atom-atom contact coverages as quantified by Hirshfeld surface analysis fingerprint plots are given. [ABSTRACT FROM AUTHOR]