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A new look at two polymorphic crystal structures of dibenzoylmethane: relationship between the crystal packing and the hydrogen atom position revealed by quantum chemistry and quantum crystallography methods
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A study of the structure of mixed micellar solutions based on heptaethylene glycol monotetradecyl ether and sodium (lithium) dodecyl sulfate by the small-angle neutron scattering method
PublicationZbadano micelizację w układach mieszanych bazujących na nowym surfaktancie niejonowym, heptaoksyetylenowanym alkoholu tetradecylowym (C14E7) i surfaktantach anionowych, dodecylosiarczanie sodu, decylosiarcznie sodu oraz dodecylosiarcznie litu za pomocą metody niskokątowego rozproszenia neutronów.Przedstawione zostały wstępne wyniki zachowania wodnych roztworów C14E7 (o dwóch stężeniach 0,17 i 0,50%) przy niewielkim udziale trzech...
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Impurity trapped exciton states related to rare earth ions in crystals under high hydrostatic pressure
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The crystal structure of (1RS,4RS,5RS,6SR)-5-cyano-5-nitro-6-phenyl-bicyclo[2.2.1]hept-2-ene
PublicationStructure of nitronorbornene derivative C14H12N2O2 synthesized in the reaction of cyclopentadiene with E-2-phenyl-1-cyano-1-nitroethene was determined by single crystal X-ray diffraction analysis. It was found that in analyzed molecule the nitro group is in endo-position whereas phenyl group have exo-ori-entation.
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Small-Angle Neutron Scattering Study of the Structure of Mixed Micellar Solutions Based on Heptaethylene Glycol Monotetradecyl Ether and Cesium Dodecyl Sulfate
PublicationThe micellization in mixed aqueous systems based on a nonionic surfactant, heptaethylene glycol monotetradecyl ether (C14E7), and an anionic surfactant, cesium dodecyl sulfate, has been investigated by small-angle neutron scattering. Preliminary data on the behavior of the C14E7 aqueous solutions (with three concentrations, 0.17, 0.5, and 1%) mixed with a small amount of anionic surfactant, cesium dodecyl sulfate, are reported.
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Explainable machine learning for diffraction patterns
PublicationSerial crystallography experiments at X-ray free-electron laser facilities produce massive amounts of data but only a fraction of these data are useful for downstream analysis. Thus, it is essential to differentiate between acceptable and unacceptable data, generally known as ‘hit’ and ‘miss’, respectively. Image classification methods from artificial intelligence, or more specifically convolutional neural networks (CNNs), classify...
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Polarimetric studies of L-arginine-doped potassium dihydrogen phosphate single crystals
PublicationConoscopic interference patterns, channelled spectra and polarimetric techniques have been used for the characterization of pure and doped (with L-arginine amino acid) potassium dihydrogen phosphate (KDP) single crystals. Experimental polarimetric data have been obtained for the frequently used wavelength of 633 nm and for two close wavelengths of 532 and 543 nm in a high-accuracy dual-wavelength polarimeter. The measurement of...
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High-accuracy polarimetric studies on lead germanate single crystals
PublicationA high-accuracy polarimetric technique has been used for the characterization of a lead germanate ferroelectric single crystal. The measurement results of the linear and circular birefringence in the [010] direction at a wavelength of 633 nm under the influence of an electric field are presented. Gyration–electric field hysteresis loops at alternative crystal positions in the polarization system have been used to determine the...
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Measuring radioactive powder samples on the high-resolution powder diffraction beamline at the European Synchrotron Radiation Facility
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Bis(ammonium) Zoledronate Dihydrate
PublicationNeutralization of 2-(1-imidazole)-1-hydroxyl-1,1`-ethylidenediphosphonic acid (zoledronic acid) by an excess of ammonia yielded bis(ammonium) zoledronate dihydrate, {C5H8N2O7P2 2−, 2(H4N+), 2(H2O)}. The product is readily soluble in water and forms monocrystals for which the X-ray structural analysis was carried out. The zoledronic anion is of double negative charge due to deprotonation of three P–OH groups and protonation of the...
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Measuring radioactive powder samples on the highresolution powder diffraction beamline at the European Synchrotron Radiation Facility
PublicationThis laboratory note describes a new sample preparation technique to enable high-resolution powder diffraction experiments at the European Synchrotron Radiation Facility on radioactive samples. The sample preparation involves setting the active material in resin and several layers of encapsulation suitable for measurement at the beamline. This has allowed low-temperature measurements on very small quantities of samples, providing...
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Optical rotation in the lithium triborate nonlinear crystal
PublicationA dual-wavelength polarimetric technique at 633 and 661 nm has been used for the characterization of a nonlinear lithium triborate (LiB3O5) nonenantiomorphous biaxial crystal. The mismatch of the crystallographic and optical coordinate systems was taken into account. The optical rotatory power for light propagation along one of the optical axes is ρ = 7.06° mm−1. The gyration tensor component along the bisector between the x and...
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Halogen bonded polypseudorotaxanes based on a pillar[5]arene host
PublicationTwo crystalline supramolecular polypseudorotaxanes were obtained by combining permethylated pillar[5]arene as a macrocyclic wheel with 1,4-bis(1-imidazolyl)butane and 1,4-bis(iodoethynyl)benzene or 1,4-diiodo-1,3-butadiyne linked by C–I⋯N halogen bonds and creating a polyrotaxane axis. The resulting highly ordered supramolecular arrays were characterized by X-ray crystallography.
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Synthesis of 3-Carbamoyl b-Lactams via Manganese(III)-Promoted Cyclization of N-Alkenylmalonamides
PublicationManganese(III)-promoted cyclization of N-alkenylmalonamides (¼N-alkenylpropanediamides) gave 3-(aryl/(alkylamino)carbonyl) b-lactams as well as 3-(aryl/(alkylamino)thiocarbonyl) b-lactams. The relative configuration of the obtained products was unambiguously determined by X-ray crystallography. The proposed method is very useful for the one-pot synthesis of a number of 3-(aryl/ (alkylamino)carbonyl) b-lactams, especially those...
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Synthesis and Spectroscopic Properties of New Bis-tetrazoles
PublicationSyntheses of N,N'-phenyltetrazole podands link with aliphatic chains containing oxygen, nitrogen and sulphur atoms, are described. The complexing properties of these compounds towards metal cations (Fe2+, Cu2+, Zn2+, Co2+, Ni2+) were investigated by absorption and infrared spectroscopy. The UV-Vis titrations were performed to estimate the stability constant values of the respective complexes with Cu2+ ion. Changes in UV-Vis absorption...
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Charge-assisted N(+)–H···(−)S hydrogen bonds in the crystal structure of selected diammonium thiophenolates.
PublicationNew salts of thiophenol with three flexible aliphatic diamines H2N(CH2)nNH2 (n = 2, 4 and 6) have been synthesized and characterized by elemental analyses, IR spectroscopy and X-ray crystallography in order to analyze their supramolecular architecture. Structural analyses indicate that in the crystals, proton transfer has occurred, with the –SH group giving (+)N–H···S(−) hydrogen bonding interaction. The structure of compound 1...
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Thermal and Chemical Expansion in Proton Ceramic Electrolytes and Compatible Electrodes
PublicationThis review paper focuses on the phenomenon of thermochemical expansion of two specific categories of conducting ceramics: Proton Conducting Ceramics (PCC) and Mixed Ionic-Electronic Conductors (MIEC). The theory of thermal expansion of ceramics is underlined from microscopic to macroscopic points of view while the chemical expansion is explained based on crystallography and defect chemistry. Modelling methods are used to predict...
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Syntheses and Structures of Transition Metal Complexes with Phosphanylphosphinidene Chalcogenide Ligands
PublicationThe reactivity of the phosphanylphosphinidene complex [(DippN)2W(Cl)(η2-P-PtBu2)]− (1) toward chalcogens (Ch = Se, S) was studied. Reactions of stoichiometric amounts of 1 with chalcogens in DME yielded monomeric tungsten complexes with phosphanylphosphinidene chalcogenide ligands of the formula tBu2P−P−Ch (Ch = Se (in 2) and S (in 5)), which can be regarded as products of the addition of a chalcogen atom to a P=W bond in starting...
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Electrochemically Obtained TiO2/CuxOy Nanotube Arrays Presenting a Photocatalytic Response in Processes of Pollutants Degradation and Bacteria Inactivation in Aqueous Phase
PublicationTiO2/CuxOy nanotube (NT) arrays were synthesized using the anodization method in the presence of ethylene glycol and different parameters applied. The presence, morphology, and chemical character of the obtained structures was characterized using a variety of methods—SEM (scanning electron microscopy), XPS (X-ray photoelectron spectroscopy), XRD (X-ray crystallography), PL (photoluminescence), and EDX (energy-dispersive X-ray spectroscopy)....
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A comparison of structural and luminescence properties of lead(II) coordination polymers with isomeric thiophenecarboxylate ligands
PublicationTwo new lead(II) coordination polymers with isomeric thiophenecarboxylates, namely [Pb(2tpCOO)2]n (1) and [Pb(3tpCOO)2(H2O)]n (2) (2tpCOO− = thiophene-2-carboxylate, 3tpCOO− = thiophene-3-carboxylate), were synthesized and characterized. Single crystal X-ray crystallography revealed a distorted pentagonal pyramidal geometry {PbO6} around Pb in 1 and a distorted dodecahedral geometry {PbO8} in 2. The distortion derived from the...
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Synteza i badania strukturalne związków kompleksowych miedzi(I) i rtęci(II) z wybranymi ligandami tioamidowymi
PublicationPrzedstawiona rozprawa doktorska poświęcona jest związkom tiokarbonylowym (wybranym tioamidom i tiomocznikom) oraz ich połączeniom kompleksowym z halogenkami miedzi(I) i rtęci(II). Istota i cel takich badań przedstawione są we wstępie pracy. W części teoretycznej opisane zostały kluczowe pierwiastki wchodzące w skład syntezowanych związków kompleksowych (siarka, miedź i rtęć), jak również tioamidy i tiomoczniki. Szczególna uwaga...
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New 2-[(4-Amino-6-N-substituted-1,3,5-triazin-2-yl)methylthio]-N-(imidazolidin-2-ylidene)-4-chloro-5-methylbenzenesulfonamide Derivatives, Design, Synthesis and Anticancer Evaluation
PublicationIn the search for new compounds with antitumor activity, new potential anticancer agents were designed as molecular hybrids containing the structures of a triazine ring and a sulfonamide fragment. Applying the synthesis in solution, a base of new sulfonamide derivatives 20–162 was obtained by the reaction of the corresponding esters 11–19 with appropriate biguanide hydrochlorides. The structures of the compounds were confirmed...
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The Metal-Free Regioselective Deuteration of 2-Methylquinolin-8-ol and 2,5-Dimethylquinolin-8-ol, Spectroscopic and Computational Studies
PublicationAbstract: Aim and Background: Introducing deuterium to a molecule is of interest to a wide variety of research, including investigation of reaction mechanisms or kinetics, analysis of drug metabolism, structural elucidation of molecules, and syntheses of isotopically labeled materials used for NMR spectroscopy and medicinal research. Objective: The transition-metal-free regioselective deuteration of 2-methylquinolin-8-ol...
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Magnetic anisotropy and structural flexibility in the f ield-induced single ion magnets [Co{(OPPh2) (EPPh2)N}2], E = S, Se, explored by experimental and computational methods
PublicationDuring the last few years, a large number of mononuclear Co(II) complexes of various coordination geometries have been explored as potential single ion magnets (SIMs). In the work presented herein, the Co(II) S = 3/2 tetrahedral [Co{(OPPh2)(EPPh2)N}2], E = S, Se, complexes (abbreviated as CoO2E2), bearing chalcogenated mixed donor-atom imidodiphosphinato ligands, were studied by both experimental and computational techniques. Specifically,...
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Glucosamine-6-phosphate synthase with an oligoHis insert
PublicationGlucosamine-6-phosphate (GlcN-6-P) synthase known also as L-Glutamine: D-fructose-6-phosphate aminotransferase (EC 2.6.1.16), catalyzes the first committed step in the amino sugar biosynthetic pathway in prokaryotic and eukaryotic organisms. The final product of this pathway is an activated precursor of numerous macromolecules containing amino sugars, including chitin and mannproteins in fungi, peptydoglican and lipopolysaccharides...
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Experimental and theoretical investigation of the reactivity of [(BDI*)Ti(Cl){η2-P(SiMe3)-PiPr2}] towards selected ketones
PublicationIn this work, we report a new type of reactivity of [(BDI*)Ti(Cl){η2-P(SiMe3)-PiPr2}] (1) towards ketones (BDI* = 2,6-diisopropylphenyl-β-methyldiketiminate ligand). In the reaction of 1 with acetone, cyclopentanone or cyclohexanone, a ketone moiety is inserted into Ti–Pphosphanyl or Ti–Pphosphido bonds to form complexes with a new C–P–P moiety, providing [(BDI*)Ti(Cl){η2-P(SiMe3)-PiPr2-C(Me)2O}] (2a), [(BDI*)Ti(Cl){η2-OC(Me)2P(SiMe3)-PiPr2}]...
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RAMAN-SCATTERING IN HEXAGONAL ICE INFLUENCED BY SYMMETRY OF CRYSTAL-LATTICE
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Hydrazinolysis Products of Selected Sugar Lactones—Crystal Structure and Microbiological Activity
PublicationCommercially available lactones, as well as those synthesized by us, turned out to be good substrates for the synthesis of sugar hydrazides. The exception was L-ascorbic acid, whose hydrazinolysis led to the formation of a hydrazinium salt, not the hydrazide as expected. The structure of all compounds was confirmed by NMR and X-ray analyses. The lower durability of hydrazinium L-ascorbate was additionally confirmed by thermogravimetric...
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Structure redetermination, transport and thermal properties of the YNi3Al9 compound
PublicationSingle crystals of completely ordered variant of the YNi3Al9 compound were grown by self-flux method with excess of aluminum. The crystal structure of the title compound was redetermined from single crystal X-ray diffraction data. The structure adopts ErNi3Al9 type, space group R32, parameters of the unit cell a = 7.2838(2) Å, c = 27.4004(8) Å. The growth of relatively large single crystals of the YNi3Al9 compound, having completely...