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An efficient semi-organic nonlinear optical bis (4-acetylanilinium) tetrachloridozincate [(C8H10NO)2 ZnCl4] (B4ATCZ) single crystal was synthesized and successfully grown by the slow evaporation method. The single-crystal X-ray diffraction data confirm that B4ATCZ crystallized into an orthorhombic crystal system (Cmca). The UV–Vis–NIR transmittance spectrum was taken to assess the optical transmission, cut-off wavelength, and bandgap energy. The TG–DSC investigation ensures that the B4ATCZ is stable up to 235 °C. The mechanical behavior of the B4ATCZ compound was determined by Vickers Microhardness analysis. The surface laser-induced damage threshold value of the grown B4ATCZ crystal was endowed to be 19.78 GW/cm2 on testing with 1064 nm Nd: YAG laser radiation. The positive photoconductive properties and charge transport mechanism of B4ATCZ crystal were analyzed through photoconductivity and dielectric studies. The electron excitation and lifetime measurements of the molecules in the B4ATCZ crystal were studied by fluorescence spectral analysis. The HOMO–LUMO analysis evidently interprets the occurrence of N–H⋯O and N–H⋯Cl intermolecular hydrogen bonds influencing the charge transfer in the system. The electrostatic potential surface reveals the possible sites for hydrogen bonding electrophilic and nucleophilic interactions. Third-order nonlinear optical activity evaluated by the Z-scan measurements indicates the self-focusing and reverse saturable absorption in the crystal. The aforesaid results affirm that the metal-organic B4ATCZ is a potential material for optoelectronic and nonlinear optical device applications. [ABSTRACT FROM AUTHOR]

Ni(NH3)4(AFT)2 [NiC6H16N18O2, AFT = 4-amino-3-(5-tetrazolate)furazan] is synthesized and characterized by elemental analysis and Fourier-transform infrared spectroscopy for the first time. X-ray diffraction measurements are used to determine the crystal structure of compound 1. The results demonstrate that compound 1 crystallized in the orthorhombic crystal system. The nickel(II) ion is six-coordinated by N atoms from two AFT-ligands and four NH3 molecules. Its thermal properties are investigated by differential scanning calorimetry and thermogravimetry-derivative thermogravimetry methods, with the results demonstrating that the differential scanning calorimetry curve exhibits two endothermic and one exothermic processes. The endothermic processes are in the range of 130–510 °C with a peak temperature of 188 °C. The temperature from 230 to 400 °C is the exothermic process in which the peak temperature is 314.58 °C. In addition, Kissinger's and Ozawa-Doyle's methods are used for calculating the non-isothermal kinetics parameters. Moreover, the apparent activation energy (E), safety, and thermal stability parameters (T SADT, T TIT, T b) for Ni(NH3)4(AFT)2 are calculated. In addition, the calculated thermodynamic functions (∆S ≠, ∆H ≠, and ∆G ≠) for the exothermic decomposition process of Ni(NH3)4(AFT)2 are 55.07 J mol−1 K−1, 196.18 kJ mol−1, and 164.90 kJ mol−1, respectively. [ABSTRACT FROM AUTHOR]

The structural response of Dy2TiO5 oxide under swift heavy ion irradiation (2.2 GeV Au ions) was studied over a range of structural length scales utilizing neutron total scattering experiments. Refinement of diffraction data confirms that the long-range orthorhombic structure is susceptible to ion beam-induced amorphization with limited crystalline fraction remaining after irradiation to 8 × 1012 ions/cm2. In contrast, the local atomic arrangement, examined through pair distribution function analysis, shows only subtle changes after irradiation and is still described best by the original orthorhombic structural model. A comparison to Dy2Ti2O7 pyrochlore oxide under the same irradiation conditions reveals a different behavior: while the dysprosium titanate pyrochlore is more radiation resistant over the long-range with smaller degree of amorphization as compared to Dy2TiO5, the former involves more local atomic rearrangements, best described by a pyrochlore-to-weberite-type transformation. These results highlight the importance of short-range and medium-range order analysis for a comprehensive description of radiation behavior. [ABSTRACT FROM AUTHOR]

The crystal structure of a potentially new mineral, the Fe2+-dominant analogue of armalcolite with the idealized formula Fe2+Ti2O5 has been solved. The sample studied originates from a pneumatolytic association related to the lamproite complex of SE Spain. The mineral is orthorhombic, space group Cmcm, the unit-cell parameters are a = 3.7325(1) Å, b = 9.7649(4) Å, c = 9.9902(3) Å, V = 364.12(2) Å3. The crystal-chemical formula (Z = 4) is in good agreement with the chemical composition of the mineral. [ABSTRACT FROM AUTHOR]

Organic single crystals of 2-Amino-5-bromopyridinium 4-hydroxybenzoate were grown by slow evaporation technique at room temperature. Single crystal XRD confirms that the crystal belongs to orthorhombic system with noncentrosymmetric space group Pna21. Functional groups presents in the synthesized compound were confirmed by FTIR analysis. UV-Vis studies shows that crystal has a lower cutoff wave length at 388 nm with an optical band gap of 2.9 eV. Dielectric studies were carried out to study the charge transport mechanism in the crystal. Photoconductivity measurements were performed. Powder SHG efficiency of the compound was found to be three times the value of KDP. [ABSTRACT FROM AUTHOR]

Superconductivity induced by a magnetic field near metamagnetism is a striking manifestation of magnetically-mediated superconducting pairing. After being observed in itinerant ferromagnets, this phenomenon was recently reported in the orthorhombic paramagnet UTe2. Here we explore the phase diagram of UTe2 under two magnetic-field directions: the hard magnetization axis b, and a direction titled by ≃25-30° from b in the (b,c) plane. Zero-resistivity measurements confirm that superconductivity is established beyond the metamagnetic field Hm in the tilted-field direction. While superconductivity is locked exactly at fields either smaller (for H | | b), or larger (for H tilted by ≃27° from b to c), than Hm, the variations of the Fermi-liquid coefficient in the electrical resistivity and of the residual resistivity are similar for the two field directions. The resemblance of the normal states for the two field directions puts constraints for theoretical models of superconductivity and implies that some subtle ingredients must be in play. In a magnetic field, superconductivity can be induced or reinforced near a metamagnetic transition, where ferromagnetic fluctuations are suspected to mediate the pairing strength of the Cooper pairs. Here, the authors investigate the superconductor UTe2 and report on the variation in the superconducting properties as the magnetic field is applied along two particular crystallographic axes and their relation to metamagnetism. [ABSTRACT FROM AUTHOR]

RbMgF3, a perovskite halide, serendipitously crystallized from a reaction between MgCl2 and TiO2 in molten RbCl/RbF eutectic flux (melting point = 546 °C) and was characterized by single crystal X-ray diffraction. RbMgF3 crystals can also be grown directly in higher yield using a molten RbCl–RbF flux layered over MgCl2 or MgF2 contained in a silver tube at 575 °C. RbMgF3 crystallizes in the hexagonal space group P63/mmc in the 6H hexagonal perovskite structure type with lattice parameters a = 5.8368(2) Å and c = 14.2087(5) Å. The crystal structure exhibits face-sharing Mg2F9 octahedra connected via corner-sharing MgF6 octahedra. Elemental composition for RbMgF3 was semi-quantitatively confirmed by energy dispersive spectroscopy (EDS). X-ray diffraction quality single crystals of RbMgF3 were grown from a molten RbCl/RbF eutectic flux at 850 °C and used for structure determination using single crystal X-ray diffraction. The compound crystallizes in the hexagonal space group P63/mmc in the 6H hexagonal structure type. [ABSTRACT FROM AUTHOR]

The crystalline structure of Zn2 (OH)PO4 (ZPOH) belongs to orthorhombic unit cell structure, space group of P21212, which has no center of symmetry. Based on the plane-wave pseudopotential ab initio method, the electronic structure, linear refractive indices and second harmonic generation (SHG) coefficients of Zn2 (OH) PO4 were calculated and the Sellmeier equations were also fitted. To verify the calculated values, ZPOH was synthesized using hydrothermal method, and the measured SHG effect is in accordance with the theoretical calculation. The ultraviolet (UV) cut-off edge and thermal stability of ZPOH were also reported for the first time. [ABSTRACT FROM AUTHOR]

The pure and metal ion (Cu2+, Zn2+ and Mg2+)-doped LAAN single crystal was developed by slow evaporation technique under ambient temperature. Cell parameters of the grown crystal were identified using single crystal X-ray diffraction analysis and found that the material crystallizes in orthorhombic crystal system with space group of P21.The presence of functional groups and the spectral properties were assessed by FTIR analysis. Transmittance spectrum reveals that the crystal has a low UV cut-off of 360 nm and has a good transmittance in the entire visible region. The band gap energy of LAAN and doped (Zn, Cu and Mg) LAAN crystals were estimated to be 3.38, 3.22, 2.75, and 3.13 eV by Tauc plot. Prevention of the recombination process of electron–hole pair was also confirmed by photoluminescence spectra analysis. The dielectric constant of pure crystal was found to be less than that of doped crystals. The AC conductivity was found to increase after doping and with the increase in temperature. Second harmonic generation efficiency of the grown crystal has been measured by Kurtz and Perry technique and it was found that Cu-doped LAAN is 3.2 times higher than that of KDP and 2.1, 1.5, and 1.8 times more prominent than pure, Zn, and Mg-doped LAAN crystals, respectively. [ABSTRACT FROM AUTHOR]

In the present work, gadolinium substitution effects on the properties of yttrium manganite YxGd1−xMn0.97Fe0.03O3 (x from 0 to 1 with a step of 0.2) synthesized by an aqueous sol–gel method have been investigated. Partial substitution of Mn3+ by 57Fe3+ in the manganite was also performed in order to investigate deeper the structural properties of synthesized compounds applying Mössbauer spectroscopy. It was demonstrated that substitution of Y3+ by Gd3+ ions leads to the changes of structural, magnetic and morphological properties of investigated system. The crystal structure gradually transformed from hexagonal to orthorhombic with an increase of Gd3+ content in the crystal lattice. The mixed phase was obtained when x = 0.6, whereas other compounds were determined to be monophasic. Magnetization measurements revealed paramagnetic behavior of all specimens, however magnetization values were found to be dependent on chemical composition of the samples. Solid solutions with orthorhombic structure revealed higher magnetization values compared to those of hexagonal samples. The highest magnetization was observed for pure GdMn0.97Fe0.03O3. Structural properties were investigated by powder X-ray diffraction, Mössbauer, FTIR and Raman spectroscopies. Morphological features of the synthesized specimens were studied by scanning electron microscopy (SEM). [ABSTRACT FROM AUTHOR]

We report the design, synthesis, and cytotoxic evaluation of a new organoruthenium(II) complex (1). Complex 1 was characterized by analytical and spectroscopic methods including single crystal X‐ray diffraction studies. Complex 1 crystallized in an orthorhombic crystal system with Pca21 space group with Ru(II) ion p‐cymene arene unit in a usual "piano‐stool" geometry. The DFT and TDFT studies were carried out to provide better insight about the spectral properties of the complex. The Hirshfeld surface analysis plots revealed significant intermolecular interactions within the crystal structure that essentially involve a network of N–H···H, O–H···O, and C–H···O linkages. DNA photocleavage activity revealed oxidative mechanistic pathway with preferential affinity toward minor groove. Cytotoxic studies of complex 1 via SRB assay revealed moderate but selective activity toward pancreatic and cervical cancer cell lines. [ABSTRACT FROM AUTHOR]

The conventional solid-state reaction method was utilized to prepare a series of superconducting samples of the nominal composition Bi2-xPb0.3WxSr2Ca2Cu3O10+δ with 0≤x≤0.5 of 50 nm particle size of tungsten sintered at 850°C for 140h in air . The influence of substitution with W NPs at bismuth (Bi) sites was characterized by the X-ray diffraction (XRD), scanning electron microscopy (SEM) and dc electrical resistivity. Room temperature X-ray diffraction analysis revealed that there exists two phases, i.e. Bi-(2223) and Bi-(2212), in addition to the impurity phases of (SrCa) 2Cu2O3, Sr2Ca2Cu7Oδ, Ca2PbO4, CaO, and WO. It was found that the crystallographic structure of all samples was orthorhombic. Lattice parameter values and the volume fraction of the (2223)-phase of the prepared samples were also calculated. The superconductivity transition temperature (Tc) for samples subjected to substitution with W NPs was found to be higher than that for the pure sample. The optimal value of W NPs content in (Bi, Pb)-2223 system was found to be at x=0.3. [ABSTRACT FROM AUTHOR]

Carbonates containing CO4 groups as building blocks have recently been discovered. A new orthocarbonate, Sr2CO4 is synthesized at 92 GPa and at a temperature of 2500 K. Its crystal structure was determined by in situ synchrotron single‐crystal X‐ray diffraction, selecting a grain from a polycrystalline sample. Strontium orthocarbonate crystallizes in the orthorhombic crystal system (space group Pnma) with CO4, SrO9 and SrO11 polyhedra as the main building blocks. It is isostructural to Ca2CO4. DFT calculations reproduce the experimental findings very well and have, therefore, been used to predict the equation of state, Raman and IR spectra, and to assist in the discussion of bonding in this compound. [ABSTRACT FROM AUTHOR]

Carbonates containing CO4 groups as building blocks have recently been discovered. A new orthocarbonate, Sr2CO4 is synthesized at 92 GPa and at a temperature of 2500 K. Its crystal structure was determined by in situ synchrotron single‐crystal X‐ray diffraction, selecting a grain from a polycrystalline sample. Strontium orthocarbonate crystallizes in the orthorhombic crystal system (space group Pnma) with CO4, SrO9 and SrO11 polyhedra as the main building blocks. It is isostructural to Ca2CO4. DFT calculations reproduce the experimental findings very well and have, therefore, been used to predict the equation of state, Raman and IR spectra, and to assist in the discussion of bonding in this compound. [ABSTRACT FROM AUTHOR]

KLiSiF6 and CsLiSiF6 were synthesized via a high‐pressure/high‐temperature synthesis route. Even though, both substances crystallize in the orthorhombic crystal system with space group Pbcn (no. 60), they show different crystal structures. Main motifs of KLiSiF6 are an [SiF6]2− and an [LiF6]5− unit. In contrast, the main motifs of CsLiSiF6 are an [SiF6]2− and an [LiF5]4− entity. Within both substances, these units are interconnected and form 3‐dimensional networks. The substances were characterized via single‐crystal and powder X‐ray diffraction, as well as infrared spectroscopy and EDX measurements. Additionally, Mn4+‐doped KLiSiF6 was analyzed by means of luminescence spectroscopy. It displays line emission in the red spectral region. The maximum emission wavelength is λmax=631 nm. [ABSTRACT FROM AUTHOR]

The yttrium (Y)-modified bismuth ferrite (BFO) ceramic compound (i.e. Bi(Fe0.85Y0.15)O3, abbreviated as BFYO15) has been synthesized through a standard solid state reaction technique. The results of its various properties, such as structural, dielectric and electrical features of Y-modified BFO were thoroughly investigated. The analysis of X-ray diffraction data confirms the phase formation of the compound, and shows the structural change from the rhombohedral to orthorhombic crystal system. The calculated average crystallite size of the sample was found to be 42 nm. The detailed studies of the dielectric parameters, impedance and ac-conductivity were performed in a wide frequency range (1–1000 kHz) at different temperatures (25–350°C). All the studies clearly show the significant change in dielectric and other electrical parameters on Y-substitution at the Fe site. Further, some of the results and electrical characteristics of the material may be used to select the material for potential device applications. [ABSTRACT FROM AUTHOR]

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Structural characteristics of solid and liquid crystalline phases of 7OS5 (4‐n‐pentylphenyl‐4′‐n‐heptyloxythiobenzoate), the achiral smectogenic mesogen with the shortest terminal carbon chain in the nOS5 homologous series, are studied by complementary methods. Simultaneously perfomed X‐ray diffraction and differential scanning calorimetry occur to be a powerful tool to study metastable phases. The single crystal structure of a high‐temperature phase, supercooled from the room temperature down to −183°C [orthorhombic crystal system; space group Pca21; a = 54.285 (5) Å, b = 5.5843 (3) Å, c = 14.841 (1) Å, Z = 8] is determined. Lamellar ordering of elongated molecules is stabilized by hydrogen bonds. Temperature dependence of unit‐cell parameters in two crystal phases as well as structural parameters of liquid crystalline phases (smectic layer spacing, tilt angle, average distance between the long axes of molecules and correlation lengths) are determined by X‐ray diffraction. The obtained results are compared with the data available for other compounds in the nOS5 homologous series. [ABSTRACT FROM AUTHOR]

The novel lead-free ferroelectric relaxor system x (Bi( Zn 2 / 3 Nb 1 / 3) O 3) (1 − x) BaTiO3 (x BZN(1 − x) BT) has received interest as a high-capacity relaxor dielectric material. Small quantities (< 10.0 mol.%) of BZN-based dopant had significant impacts on the structure of the BaTiO3 host. This study evaluates the effect of BZN additions to the BaTiO3 host up to x BZN = 10.0%. Initial additions of BZN were observed to stabilize tetragonal and orthorhombic coexistence at 295 K, alongside increasing dielectric constant. Peak dielectric constant and polarization were observed at x < 4.0%, coinciding with maximum orthorhombic intensity and a local minima in tetragonal intensity. Compositions 0 < x < 4.0% showed increasing polarization and a drop in T m and classical ferroelectric properties. No significant dielectric dispersion was observed for compositions x < 4.0% over the frequency range 5–640 kHz. Compositions at x > 4.0% showed the onset of dielectric relaxation alongside a drop in polarization coincident with a drop in the tetragonal c T / a T ratio and the onset of the cubic phase at 295 K. Peak piezoelectric, dielectric and polarization values occurred over the range 3.8% < x < 4.0%, alongside maximum orthorhombic intensity. Subsequent BZN additions showed a rapid onset of dielectric relaxation, alongside an increase in cubic intensity and a continuous drop in T m with a minima near x = 7.0%. Tetragonal presence at 295 K also vanished to zero at x = 7.0%. Polarization loops ceased showing ferroelectric characteristics at x > 5.0%, showing a transition from lossy relaxor dielectric to low-loss relaxor dielectric at x > 10.0%. [ABSTRACT FROM AUTHOR]

LaFe 1 − x Zn x O3 (x = 0.03, 0.05, and 0.07) ceramics were prepared in two steps: preparation of the powder form by a sol–gel method followed by sintering-annealing treatments to form the bulk-phase. X-ray diffraction analysis revealed that all ceramics were crystallized in the orthorhombic perovskite structure with Pbnm symmetry. Grain size distribution and morphological characteristics were investigated by scanning electron microscopy. Specific surface area was analyzed through BET–BJH methods. Electrical impedance analysis was investigated as a function of frequency at various temperatures. It was found that the electrical behavior is dominated by grain boundary contribution, i.e., electrical conductivity. The frequency dependence of the complex conductivity was analyzed through Joncher's power law and the dominance of translational motion with a sudden hopping mechanism in the electrical conduction mechanism increased with increasing Zn content. Activation energy decreased with increasing Zn content. [ABSTRACT FROM AUTHOR]

In the present study, we have focused on the growth of semi-organic single crystals, as they play a vital role in the generation of a terahertz pulse and its potential applications. The single crystals of l-histidine hydrochloride monohydrate (LMHCL) were grown by slow evaporation solution growth by using deionized water as a solvent in a controlled atmosphere. Good quality crystals of the required size were obtained within 2 weeks. To estimate the lattice dimensions and get the structural information, powder x-ray diffraction (PXRD) study was performed in which we have found that the crystal belongs to the orthorhombic crystal system with space group P212121. The functional groups and the corresponding vibrational mode were confirmed using Fourier transform infrared (FTIR) and Raman spectroscopy, respectively. To study the optical properties UV–Vis transmission spectrum and photoluminescence (PL) were recorded. It was observed that the single crystal has a high value of transmission over a long range of wavelength which signifies that the crystal is a good candidate for nonlinear optical (NLO) applications. The UV cut-off wavelength is found to be 236 nm. The grown single crystals were studied by time-domain terahertz spectroscopy (THz-TDS) for photonic applications and the refractive indices were calculated and it is found that the refractive index is nearly equal to 3.4. [ABSTRACT FROM AUTHOR]

New investigations combining single crystal‐ and synchrotron‐based powder X‐ray diffraction data revealed that Ba[Au2SnS4] crystallizes in the orthorhombic crystal system in space group C2221 instead of P21212 as reported earlier. While the principle crystal structure is not altered, there are significant differences of the interatomic distances Au‐S and Sn‐S. A salient property of this crystal structure is the partial framework composed of AuS2 dumbbells and SnS4 tetrahedra to form chains [(Au2SnS4)2–]∞ propagating in the [100] direction. Within the chains a short Au···Au separation of 2.9538(13) Å is observed, while the interchain Au···Au separation is longer at 3.383 Å. The Ba2+ cation is eightfold coordinated by S2– anions in a distorted bicapped trigonal prismatic environment BaS8. These polyhedra share all S2– anions thus generating a three‐dimensional network. This connection Scheme generates voids along [100] hosting [(Au2SnS4)2–]∞ chains. In addition, the compound has been shown to be luminescent at the blue‐green spectral range with emission maximum at approximately 21000 cm–1. [ABSTRACT FROM AUTHOR]

Benzimidazolium trichloroacetate monohydrate (BITCA) single crystals have been grown by solution growth technique. The crystal structure has been determined by single-crystal X-ray diffraction study. Benzimidazolium trichloroacetate monohydrate is crystallized in the orthorhombic crystal system with space group P212121. The FTIR and FT-Raman analyses have been used to investigate the various functional groups and their vibrational modes. The optical transparency and lower cut-off wavelength of the crystal have been determined by UV–vis spectrum. TG/DSC analyses revealed the thermal stability and decomposition of the crystal. Mechanical study confirmed the soft nature of crystal. The dielectric responses and electrical conductivity measurements have been carried out with different temperatures. The second and third-order NLO efficiency have been measured by Kurtz Perry powder and Z-Scan techniques. [ABSTRACT FROM AUTHOR]

Two imidazolium hypodiphosphates, (C3H5N2)(H3P2O6) (I) and (C3H5N2)2(H2P2O6) (II), have been synthesized and structurally characterized. In both metal‐free organic–inorganic hybrids (I) and (II), the hypodiphosphate mono‐ and dianions, (H3P2O6)− and (H2P2O6)2−, form hydrogen‐bonded frameworks of different types, to which the organic cations are linked via N—H...O and C—H...O hydrogen bonds. The purity of the compounds was confirmed by powder X‐ray diffraction. Differential scanning calorimetry of compound (I) revealed two structural phase transitions: continuous at 311.8 K [cooling/heating; from high‐temperature phase (HTP) to room‐temperature phase (RTP)] and a discontinuous one at 287.9/289.2 K [RTP → low‐temperature phase (LTP)]. Compound (I) is characterized in a wide temperature range by single‐crystal and powder X‐ray diffraction methods. Crystal structures of high‐ and low‐temperature phases are determined, which show orthorhombic (HTP, Pnna, No. 52) → monoclinic (LTP, P21/n11, No. 14, a‐axis doubled) structural change on cooling with an intermediate incommensurately modulated phase (RTP). Dynamic properties of polycrystalline (I) were studied by means of dielectric spectroscopy. The dielectric behaviour is explained by the motion of imidazolium cations. [ABSTRACT FROM AUTHOR]

For the first time, the GeSb2Te4–PbSb2Te4 section of the GeTe–Sb2Te3–PbTe quasi-ternary system is investigated by complex methods of physicochemical analysis (differential thermal, microstructural, and X-ray phase analysis with microhardness measurement and density determination) and the phase diagram is constructed. It is established that the section is a partially quasi-binary section of the GeTe–Sb2Te3–PbTe quasi-ternary system. The GeSb2Te4-based region of the solid solution (15 mol % PbSb2Te4) is revealed. The congruently melting compound GePbSb4Te8 is formed with the ratio of the initial components 1:1. Single crystals of the GePbSb4Te8 quaternary compound are formed by the method of chemical transport reactions. The unit-cell parameters of the GePbSb4Te8 compound, which crystallizes in the orthorhombic crystal system, are determined: a = 5.06 Å, b = 9.94 Å, an c = 11.62 Å. It is established by investigation of the temperature dependences of certain electrical parameters of the GePbSb4Te8 compound and (GeSb2Te4)x(PbSb2Te4)1 –x solid solution that the alloys have p-type conductivity. [ABSTRACT FROM AUTHOR]

Functionalization of metal–organic framework (MOF) ligands can tune the adsorption properties of MOFs. The adsorptions of NO, NO2, NH3, C5H5N, C4H5N, and C4H4O on pristine and five X-functionalized HKUST-1, i.e. Cu3(BTC)2 (BTC = 1,3,5-benzenetricarboxylate) (X = CH3, CH3O, NH2, NO2, and Br) are evaluated by van der Waals corrected density functional theory calculations. Despite the fact that the open metal center is the energetically preferred adsorption site for most of them, the functional group site can yield a comparable adsorption ability with the open metal center. This is particularly true for pyrrole C4H5N adsorption on CH3O-functionalized HKUST-1 where the functional group site shows stronger adsorption stability than the open metal center site, probably due to the formed hydrogen bond between pyrrole and the CH3O functional group. While the CH3- or CH3O-functionalized organic linker in these MOFs strengthens the adsorption of all the considered species, that of NO2-, Br-, or NH2-functional groups reduces, which is associated with their topologies. Among them, only CH3- or CH3O-functionalized HKUST-1 presents the fmj (orthorhombic crystal system) topology while all the others are isostructural to the pristine HKUST-1 with the tbo (twisted boracite-type, cubic) topological structure. Among six adsorbates, two basic adsorbates, C5H5N and NH3, always yield the strongest bonding strength upon adsorption on the pristine and five functionalized HKUST-1. Electronic properties including the Bader charges, electron density differences, and electron localization function were investigated to comprehend their adsorption behaviors. This work provides guidance for the proper functionalization of HKUST-1 with improved adsorption properties for specific adsorbates. [ABSTRACT FROM AUTHOR]

Single crystals of Cu 1. 7 5 Te, Cu 1. 7 0 Zn 0. 0 5 Te and Cu 1. 7 0 Cd 0. 0 5 Te compounds were synthesized by Brijmen method and their crystal structure was studied by X-ray diffraction. The hexagonal, orthorhombic aand cubic structure phases of these compounds have been determined at room-temperature. Phase transitions at high-temperatures were observed. Lattice parameters for hexagonal, orthorhombic and cubic phases have been determined in the temperature range of T = 2 9 0 –1073 K. From the temperature dependences of the lattice parameters, the coefficients of thermal expansion of the existing modifications in the main crystallographic directions were calculated. [ABSTRACT FROM AUTHOR]

Synthesis of compounds with improved physicochemical properties, including nonlinear optical phenomena such as second harmonic generation, might be considered as one of the most challenging aspects of crystal engineering. In this work, we examine the diversity of hydrogen bond networks and relative efficiencies of second harmonic generation in new noncentrosymmetric complexes comprising phenol-based hydrogen bond donors (2,5-dinitrophenol, 4-nitrophenol, 2,3,5,6-tetrachlorophenol) and pyridinium-based hydrogen bond acceptors (2-aminopyridine, 3,5-dimethylpyridine, 2,3,6-trimethylpyridine): 2-aminopyridinium 2,5-dinitrophenolate [(2APy)+·(2,5-DNP)−] (1), 2-aminopyridinium 4-nitrophenolate 4-nitrophenol [(2APy)+·(4-NP)−·(4-NP)] (2), 2,3,6-trimethylpyridinium 2,3,5,6-tetrachlorophenolate [(2,3,6C)+·(TCP)−] (3), and 3,5-dimethylpyridine 2,3,5,6-tetrachlorophenol [(3,5L)·(TCP)] (4). In compounds (1)–(3), proton transfer occurs; specifically, compounds (1) and (3) are classified as salts while compound (2) belongs to the ionic co-crystal class. Only in the case of compound (4), no evidence of proton transfer is found, attesting to its co-crystal nature. The 2,5-DNP molecule was found to possess a short intramolecular O–H⋯O hydrogen bond and crystallize in the monoclinic crystal system with space group P21. Crystal structure analysis reveals that the substituted phenol–pyridine complexes crystallize as salts linked by N–H⋯O hydrogen bonds in the orthorhombic crystal system with space group Pna21, (1) and (2), or P212121 (3), whereas (4) crystallizes in the monoclinic Cc space group as a formally molecular complex (1 : 1) linked by O–H⋯N hydrogen bonds. Additionally, the vibrational study results are also presented. These results have been discussed in the context of the hydrogen bond network present in the investigated crystals. The relative efficiencies of the second harmonic generation (SHG) process for compounds (1)–(4) were examined under 800 nm irradiation using the Kurtz–Perry powder technique. Low SHG efficiency on the order of 10−4vs. that of KDP was observed for compounds (1) and (4), which is ascribed to the self-filtering effect. For these compounds, the two-photon excited fluorescence was additionally registered. [ABSTRACT FROM AUTHOR]

A non-lead electronic sample with chemical composition Bi(Ni2/3V1/3)O3 (BNV) has been fabricated via a conventional ceramic technology. The resistive, capacitive and conducting properties of the specimen are examined experimentally. The formation of the sample with orthorhombic crystal system is ensured through X-Ray diffraction spectrum. Detailed analysis of the temperature-frequency dependent dielectric properties affirms the fabricated specimen as a dielectric. The conductivity study gives information about the nature and conduction mechanism of the fabricated dielectric. The impedance spectroscopic technique reveals the role of grain and grain boundaries on the capacitive and resistive properties of the sample. The current density based electric field characteristics show that the sample has low leakage current density (1.2 × 10−9 A/cm2). This dielectric component entails high dielectric permittivity (98 × 102), lower loss (8) and excellent excitation response to an electric field, thus it props up to be a potential component in different high-temperature industrial applications. [ABSTRACT FROM AUTHOR]

A mathematical description of crystal structure is proposed consisting of two parts: the underlying translational periodicity and the distinct atomic positions up to the symmetry operations in the unit cell, consistent with the International Tables for Crystallography. By the Cauchy–Born hypothesis, such a description can be integrated with the theory of continuum mechanics to calculate a derived crystal structure produced by solid–solid phase transformation. In addition, the expressions for the orientation relationship between the parent lattice and the derived lattice are generalized. The derived structure rationalizes the lattice parameters and the general equivalent atomic positions that assist the indexing process of X‐ray diffraction analysis for low‐symmetry martensitic materials undergoing phase transformation. The analysis is demonstrated in a CuAlMn shape memory alloy. From its austenite phase (L21 face‐centered cubic structure), it is identified that the derived martensitic structure has orthorhombic symmetry Pmmn with the derived lattice parameters ad = 4.36491, bd = 5.40865 and cd = 4.2402 Å, by which the complicated X‐ray Laue diffraction pattern can be well indexed, and the orientation relationship can be verified. [ABSTRACT FROM AUTHOR]

The article focuses on no regioselectivity for the steroid α-face in cocrystallization of exemestane with aromatic cocrystal formers based on phenanthrene and pyrene. Topics inlcude the loss of regioselectivity for the steroid α-face in cocrystallization with the monohydroxylated arenes is tentatively explained, the highly positive electrostatic surface potential of the steroid beta-face, and the diminished number of C–H groups on the α-face of exemestane compared with progesterone.

Detailed studies of structural, dielectric, and electrical characteristics of a precursor solution method synthesized, bismuth and lead titanate modified manganese titanate (MnTiO3) are reported in this communication. Analysis of X-ray diffraction data shows that MnTiO3 goes through a structural change on the addition of Bi and PbTiO3 (PT). At room temperature, MnTiO3 has a rhombohedral crystal system, which changes to an orthorhombic crystal system with the addition of bismuth in it (i.e., BiMn1/2Ti1/2O3 = BMT). On further addition of PT in BMT (i.e., 0.5 BiMn1/2Ti1/2O3–0.5PbTiO3), a stable perovskite structure with tetragonal symmetry was obtained. It is found that the addition of bismuth and lead titanate effectively reduces the grain size, and hence enhances the relative permittivity of the compound. It is further found that ferroelectricity can be induced in a non-ferroelectric MnTiO3 on the addition of Bi and PbTiO3 in it. However, the addition of bismuth and lead titanate increases the leakage current density of the compound. [ABSTRACT FROM AUTHOR]

The title compound, C16H16N2O, a potential antiparasitic agent, crystallizes in the orthorhombic Pca21 space group with unit cell parameters a= 9.912(1) Å, b= 9.035(1) Å, c= 15.681(2) Å. The crystalline structure is stabilized by weak C---H···O and C--H···Cg(π) interactions among neighboring molecules producing an efficient packing with 66.0% of occupied space. The C--H···O hydrogen bond keeps the molecules linked into supramolecular chains propagating along the a axis direction with a graph-set notation C(4), which are reinforced by C--H···Cg(π) interactions. Hirshfeld surface analysis of the intermolecular contacts reveal that the most important contributions for the crystal packing are from H··H (55.2%) and H··C/C··H (27.1%) interactions. Energy framework calculations suggest that the contacts formed between molecules are slightly dispersive in nature. [ABSTRACT FROM AUTHOR]

The Mg(BiO2)2 is the orthorhombic crystal system acting as semiconductor in electric devices. To evaluate electronic band structures, the total density of state (TDOS) and the partial density of state (PDOS), Generalized Gradient Approximation (GGA) based on the Perdew-Burke-Ernzerhof (PBE0) was used for Mg(BiO2)2. The band gap was recorded at 0.959 eV, which is supported by a good semiconductor. The density of states and partial density of states were simulated for evaluating the nature of 5s, 4d for Mg, 6s, 4f, 5d, 6p for Bi and 2s, 2p for O atom for Mg(BiO2)2 to explain the transition of the electron due to hybridization. From the PDOS, it was illustrated that the d orbital of Bi atom responses for conducting the electronic holes. [ABSTRACT FROM AUTHOR]

A non-lead electronic sample with chemical composition Bi(Ni2/3V1/3)O3 (BNV) has been fabricated via a conventional ceramic technology. The resistive, capacitive and conducting properties of the specimen are examined experimentally. The formation of the sample with orthorhombic crystal system is ensured through X-Ray diffraction spectrum. Detailed analysis of the temperature-frequency dependent dielectric properties affirms the fabricated specimen as a dielectric. The conductivity study gives information about the nature and conduction mechanism of the fabricated dielectric. The impedance spectroscopic technique reveals the role of grain and grain boundaries on the capacitive and resistive properties of the sample. The current density based electric field characteristics show that the sample has low leakage current density (1.2 × 10−9 A/cm2). This dielectric component entails high dielectric permittivity (98 × 102), lower loss (8) and excellent excitation response to an electric field, thus it props up to be a potential component in different high-temperature industrial applications. [ABSTRACT FROM AUTHOR]

New boron-rich sulfide B6S and selenide B6Se have been discovered by combination of high pressure – high temperature synthesis and ab initio evolutionary crystal structure prediction, and studied by synchrotron X-ray diffraction and Raman spectroscopy at ambient conditions. As it follows from Rietveld refinement of powder X-ray diffraction data, both chalcogenides have orthorhombic symmetry and belong to Pmna space group. All experimentally observed Raman bands have been attributed to the theoretically calculated phonon modes, and the mode assignment has been performed. Prediction of mechanical properties (hardness and elastic moduli) of new boron-rich chalcogenides has been made using ab initio calculations, and both compounds were found to be members of a family of hard phases. [ABSTRACT FROM AUTHOR]

In the frame of the studies on the phase relations in the ternary system Li–Sb–Sn at 300 °C the new ternary phase Li8SbxSn3-x (0.3 ≤ x ≤ 1.0) was synthesized and characterized predominantly by single crystal and powder X-ray diffraction. The title compound crystallizes trigonally in the space group R 3 ‾m (no. 166), the lattice parameters are a = 4.6962(11) Å and c = 31.536(6) Å. The crystal structure of Li8SbxSn3-x is described in the present paper. In addition, the stereochemical and topological relations to the phases with similar composition, namely Li13Sn5, Li5Sn2 as well as cubic Li3Sb, besides native Li are discussed. [ABSTRACT FROM AUTHOR]

Detection of hazardous chemicals is crucial for a healthy and safe environment as well as for the well-being of humans. A confluence of chemistry and engineering continues to improve the sensitivity and selectivity for several classes of harmful chemicals with the promise of cheap and portable sensing. Herein, following the function-oriented research strategy, eight novel lanthanide coordination polymers (Ln-CPs) have been successfully assembled with the framework composition [Ln(2,5-FDC)0.5(Adip)(H2O)2] (Ln = Nd (1), Sm (2), Eu (3), Gd (4), Tb (5), Dy (6), Ho (7), Er (8), 2,5-FDC2− = furan-2,5-dicarboxylate, Adip2− = Adipate) under solvothermal synthesis conditions. The structural analysis indicates that all the eight CPs have the same structural features. All compounds crystallize in the orthorhombic crystal system (space group Pnma) with point symbol {33·44·53} and consist of 2D cem topological type. The linkers 2,5-FDC2− and Adip2− exhibit μ2-κ4,η1:η1:η1:η1 and μ3-κ5,η2:η1:η1:η1 coordination modes respectively. The as-synthesized polymers were characterized by powder X-ray crystallography, infrared spectroscopy, thermogravimetric analysis, and photoluminescence studies. CP-3 and CP-5 are promising luminescent lanthanide coordination polymers (Ln-CPs) and function as efficient sensors for the detection of nitroaromatic compounds at the ppm level in mix N,N′-dimethyl formamide-aqueous medium via the luminescence quenching mechanism. [ABSTRACT FROM AUTHOR]

Single crystal x-ray diffraction measurements on both as-grown as well as oxygenated single crystals of an aluminium doped high temperature superconductor YBa2Cu3−xAlxO6+δ revealed the crystal structure to be orthorhombic with space group Pmmm, in contrast to, tetragonal crystal structures corresponding to space group P4/mmm, previously reported for as-grown YBa2Cu3−xAlxO6+δ, and conflicting structures on oxygenated YBa2Cu3−xAlxO6+δ. The orthorhombic crystal structure was confirmed by powder x-ray diffraction that showed the presence of two peaks corresponding to (020) and (200) reflections associated with orthorhombic structures of space group Pmmm, instead of a single (200) reflection corresponding to tetragonal crystal structures with space group P4/mmm. All the as-grown crystals were found to be superconducting. An oxygen-vacancy cluster distribution model is proposed to explain the differences in the obtained magnetisation hysteresis loop and the broad superconducting transition temperature. The model proposes the existence of two oxygen deficient clusters of (Al-..-Cu-O-Cu)n and (Cu-O-Cu-..)n juxtaposed with each other whose number and size vary as the as-grown single crystals of YBa2Cu3−xAlxO6+δ are subjected to oxygenation. X-ray photoelectron spectroscopy measurements showed the existence of two distinct peaks in each of the spectrum of O, Cu, Y and Ba in YBa2Cu3−xAlxO6+δ crystals corresponding to the two different types of clusters. The relative intensities of each XPS peak was found to decrease in the oxygenated crystals as compared to the as-grown ones confirming the change in the number and size of clusters in the as-grown crystals after oxygenation. [ABSTRACT FROM AUTHOR]

Strontium-doped neodymium orthoferrites belong to the perovskite type of materials of a wide range of interests and applications. This material has an orthorhombic perovskite crystal system of space group (Pbnm) no. 62. Nd0.6Sr0.4FeO3 is synthesized using the co-precipitation method, and the resulting precipitated powder was fired at different temperatures to control the nano-crystalline size. The effect of the nano-crystalline size on the structure and the electrical properties were studied. The EDS spectra confirmed that the compound was formed according to the suggested calculations. SEM micrographs showed the homogeneity of the nano grain size in the compound. The nano-crystalline size of the prepared samples, fired at 705 °C and at 850 °C were 40 nm and 90 nm, respectively. Nd0.6Sr0.4FeO3 showed a semiconducting behavior according to the exponential dependence of resistivity on temperature in the range from 350 K up to 473 K. The temperature independence of impedance is found at high frequencies starting from 0.5 MHz. The frequency dependence–activation energy is found in the temperature range from 350 K up to 473 K. The found decrease in AC resistivity with frequency increase for Nd0.6Sr0.4FeO3 showed that the hopping mechanism occurred in the charge carrier transfer. [ABSTRACT FROM AUTHOR]

This paper presents the results of mineralogical and crystallographic studies in the first Russian finding of a mineral belonging to the fluoride class, viz., knasibfite, which was found in fumarolic deposits discharged during the Great Tolbachik Fissure Eruption. We investigated its crystal structure to corroborate the fact that knasibfite is orthorhombic, sp. gr. Imm2; a = 17.181 (2), b = 5.537 (4), c = 9.205 (7) Å, V = 875 (1) Å3. The structural features that can be seen in this mineral classify it as belonging to a special group of compounds that has inherited its structure from a high temperature modification or from the medium where it crystallized. [ABSTRACT FROM AUTHOR]

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The ternary system Sc-Al-Cu system has been investigated in this work. Several alloys with various compositions have been prepared by arc-melting from the elements and studied by X-ray diffraction. An icosahedral quasicrystal of formula ScAl2.4Cu3.2 has been identified using the reciprocal space reconstructed from its diffraction images. The diffraction data collected for several single crystals led to solve and refine five crystal structures: cubic ScAlCu2 (Fm 3 ¯ m), hexagonal ScAl1.1Cu0.9 (P 6 ¯ m2), hexagonal ScAl2.4Cu2.9 (P63/mmc), tetragonal ScAl5.3Cu6.7 (I4/mmm) and orthorhombic ScAl2.2Cu3.4 (Cmmm). Almost all these structures are characterised with copper/aluminum atomic mixing at most of the crystallographic sites and the atomic arrangements are favourable to the existence of stoichiometry ranges for the compounds. These results, providing new single crystal data sets for these ternary compounds, clarify and confirm the structures previously reported (from crystal or powder data). [ABSTRACT FROM AUTHOR]

The title compound, N-(2-pyridylmethyl)-L-alanine) zinc(II), [Zn(C10H11N3O2S)], a coordination polymer derived from the mixed ligands, N-(2-pyridylmethyl)-L-alanine (HL1) and ammonium thiocyanide (L2) has been synthesized and characterized by IR spectroscopy, 1H-NMR, elemental analysis, thermogravimetric analysis and single crystal x-ray structure determination. The single crystal X-ray structure analysis of the title compoundreveals a molecular polymeric compound that crystallizes in the orthorhombic crystal system and P2(1)2(1)2(1) space group. The ligand acts as a bridge between adjacent zinc(II) centres, each of which adopts a five-coordinate geometry. Zinc bonds to two N atoms and one O atom of HL1, one N atom of L2 and one O atom of another HL1 ligand. This is confirmed by IR spectroscopy. Thermogravimetric analysis shows a one-step decomposition of the complex to leave a zinc sulfide residue. [ABSTRACT FROM AUTHOR]

Single crystal of a potential non-linear optical material, l-histidinium 4-methylbenzene sulfonate (LHMS), with dimensions 55 × 10 × 13 mm3 was persuasively grown by slow evaporation solution growth technique. The titular compound proficiently crystallizes in orthorhombic crystal system with non-centrosymmetric space group, P212121. Theoretical DFT estimations were carried out to calculate the bond lengths and bond angles of the grown crystal. Theoretical calculation was made for obtaining frontier energy gaps in contemplation of understanding the charge deportation occurring in the molecule. Orbital that bonds naturally provides an expedient basis for the analysis of charge deportation in the molecular system. The UV–Vis–NIR spectrum was recorded to study the optical transparency of the grown crystal and it is found that the grown crystal is transparent in the entire visible region with the lower cutoff wavelength at 230 nm. Thermal behavior of the crystal was scrutinized using thermogravimetric analysis (TG) and differential thermal analysis (DTA). Vickers microhardness test was carried out along three different planes to evaluate the anisotropic mechanical behavior of the grown crystal and it is found that the title material belongs to hard material category. [ABSTRACT FROM AUTHOR]

In this study, the new 2D organic compound [PSA2][BPP2] (psa=phenol-4-sulfonic acid, bpp=1,3-Bis(4-pyridyl)propane was hydrothermally synthesized and characterized by single-crystal Xray diffraction, powder X-ray diffraction (PXRD), elemental analysis, and solid-state UV-vis absorption spectra. The crystal structure analysis of the compound indicates that complex crystallizes in the orthorhombic crystal system Pca21 space group and its asymmetric unit consists of two discrete psa and bpp ligand. The ring of phenol and pyridyl groups is almost planar. Additionally, crystal structure of the compound is linked via intermolecular O - H...O and C - H...O hydrogen bonds as well as intramolecular C-H...π and between the bpp molecules π - π interactions, which form two-dimensional structure and provide structural stability. [ABSTRACT FROM AUTHOR]

Semi-organic lithium hydrogen phthalate dihydrate crystal has been grown using a slow evaporation solution growth technique. It belongs to the orthorhombic crystal system. The nucleation cure is calculated for different temperatures. The various intermolecular interactions were found out using Hirshfeld surfaces. The vibrational analysis was affirmed using FTIR and FT-Raman spectra. The lithium hydrogen phthalate dihydrate has good transmittance in the UV–Vis–NIR region. The decomposition happens in various stages. The etch pit was determined using the water solvent. The surface damage happens due to the decomposition of the crystal. [ABSTRACT FROM AUTHOR]

In this study, a group of submicro BaTiO 3 ceramics ranging from 330 nm to 1.05 μm was successfully prepared by a two-step sintering process and the dependence of electric and mechanical properties on grain size was investigated. By dynamic mechanical analysis (DMA), phase transitions and grain size effects on modulus and internal friction were clearly detected. A clear low-frequency relaxation behavior induced by Debye relaxation was characterized in orthorhombic phase for fine BT ceramics. Furthermore, Arrhenius relationship was applied to theoretically analyze the relaxation peak, for which 90° domain wall motion was considered to be responsible. Another anomaly peak around 70 °C became more obvious after annealing in oxygen atmosphere, which was caused by the surface charge release, the interaction between domain walls and stress, and size effect. [ABSTRACT FROM AUTHOR]

The crystal structure of a new superconductor UTe2 has been investigated using single‐crystal neutron diffraction for the first time at the low temperature (LT) of 2.7 K, just above the superconducting transition temperature of ∼1.6 K, in order to clarify whether the orthorhombic structure of type Immm (No. 71), reported for the room‐temperature (RT) structure persists down to the superconducting phase and can be considered as a parent symmetry for the development of spin‐triplet superconductivity. In contrast to the previously reported phase transition at about 100 K [Stöwe (1996). J. Solid State Chem. 127, 202–210], our high‐precision LT neutron diffraction data show that the body‐centred RT symmetry is indeed maintained down to 2.7 K. No sign of a structural change from RT down to 2.7 K was observed. The most significant change depending on temperature was observed for the U ion position and the U–U distance along the c direction, implying its potential importance as a magnetic interaction path. No magnetic order could be deduced from the neutron diffraction data refinement at 2.7 K, consistent with bulk magnetometry. Assuming normal thermal evolution of the lattice parameters, moderately large linear thermal expansion coefficients of about α = 2.8 (7) × 10−5 K−1 are estimated. [ABSTRACT FROM AUTHOR]

The Aurivillius phases (APs) [Bi2O2] 2 + [ A m − 1 B m O 3 m + 1 ] 2 − are well-known ferroelectrics with high Curie temperatures. High-temperature piezoceramics Bi 3 − x GdxTiNbO9(BiGdTiNb, x = 0 , 0.1, 0.2, 0.3) were prepared by a solid-state reaction method. The structural and electrophysical characteristics of BiGdTiNb ceramics have been studied. According to the data of powder X-ray diffraction, all the compounds are single-phase with the structures of two-layer APs (m = 2) with the orthorhombic crystal lattice (space group A 2 1 a m). The temperature dependence of the relative permittivity ε ∕ ε 0 (T) of the compounds was measured and showed that the Curie temperature of perovskite-like oxides Bi 3 − x GdxTiNbO9 increases linearly with an increase in the substitution parameter x to T C = 9 5 0 ∘ C. The activation energies of charge carriers have been found in different temperature ranges. [ABSTRACT FROM AUTHOR]