46 results match your criteria: "STC 'Institute for Single Crystals'[Affiliation]"

Optical and Mechanical Properties of Layered Infrared Interference Filters.

Sensors (Basel)

October 2022

Private company "Modern Optical Technology", 16 Obolonskyi Ave., 04205 Kyiv, Ukraine.

The design and manufacturing technology of interference-absorbing short-wave filters based on a layered composition of Si-SiO on a sapphire substrate of various shapes was developed. A transition layer of SiO was applied to the surface of the substrate, alternating with layers of Si-SiO with an odd number of quarter-wave layers of materials with high (Si) and low refractive indices (SiO), and the application of an outer layer of SiO as an appropriate control of the materials' thickness. The optical properties of the infrared light filter were studied.

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New lanthanide dimethyl-N-benzoylamidophosphate (HL) based tetrakis-complexes NEt [LnL ] (Ln =La, Nd, Sm, Eu, Gd, Tb, Dy) are reported. The complexes are characterized by means of NMR, IR, absorption, and luminescent spectroscopy as well as by elemental, X-Ray, and thermal gravimetric analyses. The phenyl groups of the four ligands of the complex anion are directed towards one side, while the methoxy groups are directed in the opposite side, which makes the complexes under consideration structurally similar to calixarenes.

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Mixed-metal phosphates KNaTiFe(PO) and KNaTiFe(PO) with a langbeinite framework.

Acta Crystallogr E Crystallogr Commun

December 2021

Shenzhen Key Laboratory of Solid State Batteries, Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen 518055, People's Republic of China.

Single crystals of the langbeinite-type phosphates KNaTiFe(PO) and KNaTiFe(PO) were grown by crystallization from high-temperature self-fluxes in the system NaO-KO-PO-TiO-FeO using fixed molar ratios of (Na+K):P = 1.0, Ti:P = 0.20 and Na:K = 1.

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Structural features of the oxidonitridophosphates K (PO)N ( = Al, Ga).

Acta Crystallogr E Crystallogr Commun

December 2021

Department of Inorganic Chemistry, Taras Shevchenko National University of Kyiv, 64/13, Volodymyrska str., 01601, Kyiv, Ukraine.

Cubic crystals of tripotassium aluminium (or gallium) nitridotriphosphate, K (PO)N ( = Al, Ga), were grown by application of the self-flux method. In their isostructural crystal structures, all metal cations and the N atom occupy special positions with site symmetry 3, while the P and O atoms are situated in general positions. The three-dimensional framework of these oxidonitridophosphates is built up from [ O] octa-hedra linked together (PO)N groups.

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Predictive QSAR models for the search of new adenosine A receptor antagonists were developed by using OCHEM platform. The predictive ability of the regression models has coefficient of determination q  = 0.65-0.

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Cytotoxicity, Retention, and Anti-inflammatory Effects of a CeO Nanoparticle-Based Supramolecular Complex in a 3D Liver Cell Culture Model.

ACS Pharmacol Transl Sci

February 2021

Institute of Chemical Technologies and Analytics and Institute of Applied Synthetic Chemistry, Faculty of Technical Chemistry, Vienna University of Technology, Getreidemarkt 9, 1060 Vienna, Austria.

Both cerium oxide (CeOx) nanoparticles and mefenamic acid (MFA) are known anti-inflammatory agents with hepatoprotective properties and are therefore prescribed for one of the major diseases in the world, nonalcoholic fatty liver disease (NAFLD). To study the potential cytotoxicity and anti-inflammatory effects as well as drug retention of a potential therapeutic CeOx/MFA supramolecular complex, a well-standardized hepatic (HepG2) spheroid model was used. Results showed that the highest cytotoxicity for the CeOx/MFA supramolecular complex was found at 50 μg/mL, while effective doses of 0.

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We found that 1-phosphanyl-1,2,3,4-tetrahydroquinazolines undergo ring enlargement. Their treatment with trifluoroacetic or hydrochloric acid afforded diazaphosphepinium salts. Deprotonation of these salts gave the corresponding neutral diazaphosphepines.

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A series of pentanuclear lanthanide complexes LnL(μ-L)(μ-OH)(μ-OH) (Ln = Nd, Dy, Ho, Er, Yb; L = dimethyl -benzoylamidophosphate ion, [CHC(O)-N-P(O)(OCH)]) was obtained by the reaction of sodium dimethyl -benzoylamidophosphate with the corresponding lanthanide nitrates. The pentanuclear cores formed as a result of self-arrangement and their composition did not depend on the lanthanide ion. The complexes and sodium dimethyl -benzoylamidophosphate have been characterized by single-crystal X-ray diffraction.

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In order to determine the regularities of the structure-analgesic activity relationship, the peculiarities of obtaining, the spatial structure, and biological properties of 4-methyl-2,2-dioxo-1-2λ⁶,1-benzothiazine-3-carboxylic acid and some of its derivatives have been studied. Using nuclear magnetic resonance (NMR) spectroscopy and X-ray diffraction analysis, it has been proven that varying the reaction conditions using alkaline hydrolysis of methyl 4-methyl-2,2-dioxo-1-2λ⁶,1-benzothiazine-3-carboxylate makes it possible to successfully synthesize a monohydrate of the target acid, its sodium salt, or 4-methyl-2,2-dioxo-1-2λ⁶,1-benzothiazine. The derivatographic study of the thermal stability of 4-methyl-2,2-dioxo-1-2λ⁶,1-benzothiazine-3-carboxylic acid monohydrate has been carried out; based on this study, the optimal conditions completely eliminating the possibility of unwanted decomposition have been proposed for obtaining its anhydrous form.

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Due to the high reactivity towards various C-nucleophiles, trifluoromethylketimines are known to be useful reagents for the synthesis of α-trifluoromethylated amine derivatives. However, decarboxylative reactions with malonic acid and its mono(thio)esters have been poorly investigated so far despite the potential to become a convenient route to β-trifluoromethyl-β-amino acid derivatives and to their partially saturated heterocyclic analogues. In this paper we show that 4-trifluoromethylpyrimidin-2(1)-ones, unique heterocyclic ketimines, react with malonic acid under organic base catalysis to regioselectively provide either Michael- or Mannich-type decarboxylative addition products depending on solvent polarity.

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Novel modification of anhydrous transition metal oxalates from powder diffraction.

Acta Crystallogr C Struct Chem

November 2017

STC Institute for Single Crystals, National Academy of Science of Ukraine, 60 Nauky Avenue, Kharkiv 61001, Ukraine.

The known metal-CO structures may be divided into two modifications, α and β. The α-modification has an order-disorder struxture, revealing one-dimensional disordering of the metal-oxalate chains, and the β-modification is ordered. The crystal structures of orthorhombic γ-MnCO {poly[μ-oxalato-manganese(II)]; space group Pmna, a = 7.

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The asymmetric unit of [La(CHNOPS)(CHN)] is created by one La ion, three deprotonated -{bis-[meth-yl(phen-yl)amino]-phosphor-yl}benzene-sulfonamidate () ligands and one 1,10-phenanthroline (Phen) mol-ecule. Each La ion is eight-coordinated (6O+2N) by three phosphoryl O atoms, three sulfonyl O atoms of three ligands and two N atoms of the chelating Phen ligand, leading to the formation of six- and five-membered metallacycles, respectively. The lanthanum coordination polyhedron has a bicapped trigonal-prismatic geometry.

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The question of the activation energy of phase transitions in lyotropic liquid crystal phases of model phospholipid membranes was considered. In our experiments, we obtained DSC thermograms of hydrated DPPC and DMPC at different scanning rates, and activation energy values were determined by a modification of Kissinger non-isothermal kinetics method. Using this approach the equivalent order of reaction corresponding to the phase transition can be determined alongside the activation energy.

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As potential new analgesics, the corresponding 4-hydroxy-2,2-dioxo-1-2λ⁶,1-benzothiazine-3-carboxanilides have been obtained by amidation of ethyl 4-hydroxy-2,2-dioxo-1-2λ⁶,1-benzothiazine-3-carboxylate with aniline and its halogenated analogsin boiling dry xylene. The peculiarities of the mass and nuclear magnetic resonance (¹Н and С) spectra of the synthesized compounds are discussed. Using X-ray diffraction analysis, the ability of the compounds to form stable solvates with ,-dimethylformamide has been shown on the example of 4-bromo-substituted derivative.

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In the mol-ecular structure of the title compound, [CaNa(CHClNOP)(HO)], the Ca ion has a slightly distorted octa-hedral coordination environment defined by six O atoms which belong to the carbonyl and phosphoryl groups of the three coordinating ligands. Two Cl atoms of CCl groups and four O atoms form the coordination environment of the Na ion: three from the carbonyl groups of ligands and one O atom from a coordinating water mol-ecule. In the crystal, the bimetallic complexes are assembled into chains along the -axis direction O-H⋯O hydrogen bonds that involve the coordinating water mol-ecules and the phosphoryl groups.

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In the title compound, [U(C13H9N4O)(NO3)O2(H2O)]·CH3CN·H2O, the U(VI) atom is seven-coordinated in a distorted penta-gonal-bipyramidal N2O5 manner by one tridentate triazole ligand, one monodentate nitrate anion and one water mol-ecule in the equatorial plane and by two uran-yl(VI) O atoms in the axial positions. In the crystal, the U(VI) complex mol-ecule is linked to the water and aceto-nitrile solvent mol-ecules through N-H⋯N, O-H⋯O and O-H⋯N hydrogen bonds, forming a sheet structure parallel to the bc plane. The sheets are further linked by an additional O-H⋯O hydrogen bond, forming a three-dimensional network.

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The influence of molybdenum content in the solid solutions of Bi1-x/3V1-xMoxO4 (x = 0.05-0.20) on the morphology, band gap, structure and light-driven water oxidation properties has been studied by scanning electron microscopy, X-ray powder diffraction and vibrational spectroscopy (Raman and infrared).

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We extend excited-state structural analysis to quantify the charge-resonance and multi-exciton character in wave functions of weakly interacting chromophores such as molecular dimers. The approach employs charge and spin cumulants which describe inter-fragment electronic correlations in molecular complexes. We introduce indexes corresponding to the weights of local, charge resonance, and biexciton (with different spin structure) configurations that can be computed for general wave functions thus allowing one to quantify the character of doubly excited states.

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Article Synopsis
  • Potassium rubidium cobalt(II)/titanium(IV) tris-(orthophosphate) was synthesized using a high-temperature crystallization technique.
  • The compound features a langbeinite-type structure, combining mixed Co/Ti(IV) octahedra and PO4 tetrahedra in a three-dimensional framework.
  • K(+) and Rb(+) cations are randomly distributed in large cavities, with each surrounded by 12 oxygen atoms.
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A set of novel SO2-containing azabicyclo[3.n.1]alkanes has been synthesized by the double-Mannich annulation of of the corresponding monocyclic S-ketones.

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In the molecular structure of the title compound, [NaNi(C18H18N2O4)(NO3)(CH3OH)], the Ni(2+) ion has a slightly distorted square-planar coordination environment defined by two N and two O atoms which belong to a Schiff base ligand, viz. 6,6'-dimeth-oxy-2,2'-[ethane-1,2-diylbis(nitrilo-methanylyl-idene)]diphenolate. Seven O atoms form the coordination environment of the Na(+) ion: four from the Schiff base ligand, two from a bidentate chelating nitrate anion and one O atom from a coordinating methanol mol-ecule.

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In the title compound, C9H6F3NOS, the 1,3-benzo-thia-zole ring system is essentially planar, with an r.m.s.

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The title solvate, C20H14N4O4S·C3H7NO, comprises a stereogenic centre but the centrosymmetric space group causes the presence of the racemate in the crystal. The spiro-joined fragments are almost orthogonal, with a dihedral angle of 86.8 (2)° between the mean planes of the pyrane ring and the dihydroindolone ring system.

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The solid solution K3.84Ni0.78Fe3.19(PO4)5.

Acta Crystallogr Sect E Struct Rep Online

July 2014

Department of Inorganic Chemistry, Taras Shevchenko National University of Kyiv, 64/13, Volodymyrska St, 01601 Kyiv, Ukraine.

The title compound, tetra-potassium tetra-[nickel(II)/iron(III)] penta-kis-(orthophosphate), K3.84Ni0.78Fe3.

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Tetra-kis(μ3-2-{[1,1-bis-(hy-droxy-meth-yl)-2-oxidoeth-yl]imino-meth-yl}-6-nitro-pheno-lato)tetra-copper(II).

Acta Crystallogr Sect E Struct Rep Online

February 2014

STC 'Institute for Single Crystals', National Academy of Sciences of Ukraine, 60 Lenina Avenue, Kharkiv 61001, Ukraine.

The title cluster, [Cu4(C11H12N2O6)4], was obtained from the Cu(0)-FeCl2·4H2O-H4 L-Et3N-DMF reaction system (in air), where H4 L is 2-hy-droxy-methyl-2{[(2-hy-droxy-3-nitro-phen-yl)methyl-idene]amino}-propane-1,3-diol and DMF is di-methyl-formamide. The asymmetric unit consists of one Cu(2+) ion and one dianionic ligand; a -4 symmetry element generates the cluster, which contains a {Cu4O4} cubane-like core. The metal ion has an elongated square-based pyramidal CuNO4 coordination geometry with the N atom in a basal site.

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