Journal articles: 'Oxygen and sodium nuclei structure'

1

Bosáček, Vladimír, Stanislav Vratislav, and Mája Dlouhá. "Bridging Methoxy Groups in NaY, NaX and NaLSX Zeolites." Collection of Czechoslovak Chemical Communications 69, no. 8 (2004): 1537–52. http://dx.doi.org/10.1135/cccc20041537.

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Distribution of chemisorbed methyl groups and sodium cations in the structure of NaY, NaX and NaLSX zeolites was estimated by neutron diffraction. Chemisorbed methyl groups were prepared in the structure by reaction of methyl iodide with reactive sodium cations available in SII and SIII positions of faujasites. Methyl cations CH3+, formed in the reaction, react immediately with the lattice oxygen forming surface bonded methyl groups in bridging configuration. 13C NMR signals of chemisorbed surface species and their linear dependence on the intermediate electronegativity of the zeolite lie in the interval from 53 ppm for most basic CsLSX to 58 ppm TMS for stabilized and acid leached sample of H,NaY-St. Changes in the distribution of structural sodium cations in the lattice after chemisorption of methyl cations have been detected. C-O distances in surface methoxy groups in void cavities were longer than in ordinary crystalline organometallic compounds with bridging methoxy groups. The location of chemisorbed methyl groups at the O1 lattice oxygen type was most probable for NaY. Nuclear densities of chemisorbed methyl groups were detected in NaX at O1 and at O4 lattice oxygens. The origin of the split signal at 58 ppm on NaX and NaLSX samples has been discussed.

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Starratt, Alvin N., Edmund W. B. Ward, and J. B. Stothers. "Coprinolone and Δ6-coprinolone: new sesquiterpenes from Coprinus psychromorbidus." Canadian Journal of Chemistry 67, no. 3 (March 1, 1989): 417–27. http://dx.doi.org/10.1139/v89-065.

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The structure of coprinolone (1), an oxygen-bridged protoilludane from the W2 isolate of the fungus Coprinuspsychromorbidus, has been elucidated by chemical transformations and detailed 1H and 13C magnetic resonance studies, including homo- and heteronuclear correlation spectra. The 1H–1H coupling data and nuclear Overhauser difference spectra for 1 and derived isomers led to the establishment of its stereochemistry. A second metabolite was identified as Δ6-coprinolone (20) by spectroscopic results. Confirmatory evidence in support of the structures was obtained from the labelling patterns of the compounds from cultures supplemented with sodium [1,2-13C2]acetate. Keywords: coprinolone, Δ6-coprinolone, protoilludane, sesquiterpenes, NMR.

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Wolfe, Saul, Raymond John Bowers, Hee-Sook Shin, Chang-Kook Sohn, Donald Fredric Weaver, and Kiyull Yang. "Phenceptin: a biomimetic model of the phenytoin receptor." Canadian Journal of Chemistry 66, no. 11 (November 1, 1988): 2751–62. http://dx.doi.org/10.1139/v88-425.

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5,5-Diphenylhydanytoin (phenytoin) is the most widely used anticonvulsant drug, but has many side effects. Although its chemical mode of action is unknown, phenytoin is believed to function primarily by interference with the transport of sodium ions across the neuronal membrane. Structure–activity and lipophilicity–activity studies suggest that the drug interacts with its receptor through hydrogen bonding to the N3—C4 amide bond, and an aromatic–aromatic interaction with the C5 substituent. Since sodium channels are cysteine-rich peptides, whose function depends upon the cysteine[Formula: see text]cystine redox process, it has been hypothesized that the action of the phenytoin receptor may be mimicked by a properly designed cyclodepsipeptide containing a cystinyl moiety, a cavity lined with five oxygen atoms oriented in the trigonal-bipyramidal manner appropriate for selective transport of sodium ions, and a site for the binding of phenytoin. A computer programme and strategy were developed to permit the three-dimensional structures of potential target molecules to be viewed, prior to synthesis. Use of this programme led to the discovery of Boc-L-cystinyl-glycyl-L-prolyl-glycyl-L-prolyl-L-cystine-OCHPh2. This compound, termed phenceptin, was synthesized from a linear precursor containing tert-butoxycarbonyl protection at the N-terminus, benzhydryl ester protection at the C-terminus, and trityl protection at sulfur. Detritylation and cyclization to phenceptin were accomplished with iodine in methanol–pyridine. Using an n-octanol membrane to study the kinetics of ion transport, phenceptin was found to transport sodium ions selectively, but only in its oxidized, cyclic form. This transport was inhibited significantly by one mol-equiv. of phenytoin, and not at all by biologically inactive analogs of the drug. The nature of the binding of phenytoin to phenceptin was examined by nuclear magnetic resonance, in n-C8D17-OH solvent, and found to involve hydrogen bonding of the drug to a glycine residue whose oxygen atom is involved in complexation to sodium ions.

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Dickson, R. S., and J. A. Weil. "The magnetic properties of the oxygen-hole aluminum centres in crystalline SiO2. IV. [AlO4/Na]+." Canadian Journal of Physics 68, no. 7-8 (July 1, 1990): 630–42. http://dx.doi.org/10.1139/p90-094.

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The centre [AlO4/Na]+, formed in α-quartz by X irradiation at 77 K, contains an aluminum ion substituted for a silicon ion, with an electron hole on a nearest-neighbor oxygen ion, and an interstitial sodium ion, which acted as a charge compensator before loss of the electron. Electron paramagnetic resonance spectra of this centre at 35 K have yielded spin-Hamiltonian nuclear quadrupole and hyperfine parameter matrices [Formula: see text], Ā(23Na), and [Formula: see text], in addition to matrices [Formula: see text] and Ā(27Al) more accurate than those measured previously. The line width anisotropy is parameterized by an appropriate matrix W. Hartree–Fock molecular orbital geometry optimizations on a small model cluster, [Al(OH)4Na]+, and hyperfine matrices calculated for the lowest energy configuration, confirm that [AlO4/Na]+ has the same type of structure as [AlO4/H]+ and [AlO4/Li]+; the hole is on an oxygen ion linked to the aluminum ion by a "short" bond, and the sodium ion is in the nearby c-axis channel on the long-bond side of the aluminum ion. The thermal decay of [AlO4/Na]+ to [AlO4]0, measurable at 154 K and above, and the subsequent formation of centres [GeO4/Na]0 from [GeO4]− were studied.

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Yan, Lu, and Fan Ping. "Synthesis and Study of 4, 4-12-12 Alkyl Phenol Polyoxyethylene Sulfonate Gemini Surfactant." Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) 12, no. 4 (October 28, 2019): 262–74. http://dx.doi.org/10.2174/2405520412666190723112325.

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Background: Gemini surfactants have good prospect of application development in various fields for their superior performance in foaming, wettability, and emulsification with lower critical micelle concentration (CMC) than conventional mono-surfactants. Objective: The purpose of this study was to synthesize an ionic sulfonate Gemini surfactant, which is mainly used as an oil flooding agent, to improve oil recovery and reduce oil production cost. Methods: With 4-dodecyl phenol, diethylene glycol and triethylene glycol as the raw materials to synthesize two sulfonate Gemini surfactants. The single factor experiment combined with Box-Behnken center composite experimental design, the optimum reaction conditions were determined. The optimal reaction condition of sulfonation was determined by orthogonal test. The product structure was characterized by nuclear magnetic resonance and infrared. Results: The mass fraction of sodium hydroxide ω(NaOH), temperature and the quality ratio of hexadecyl trimethyl ammonium bromide to dodecyl phenol were 18%, 93.5°C and 14.2%, respectively. Under the condition of ice bath, the molar ratio of chlorosulfonic acid to 4, 4- 12-12 alkyl phenol polyoxyethylene ether was 2.02:1 and reaction for 5h. The critical micelle concentration was determined to be 2×10-4, 1.05×10-4, respectively. Conclusion: Two sulfonate Gemini surfactants, namely 5, 5-dilauryl alkyl-2,2'-(diethylene glycol oxygen base) sodium diphenyl sulfonate and 5,5-dilauryl alkyl-2,2'-(triethylene glycol oxygen base) sodium diphenyl sulfonate (recorded as III and IV, respectively) were synthesized. The synthesized surfactants have excellent emulsification ability.

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Stefanovsky, Sergey V., Andrey A. Shiryaev, Michael B. Remizov, Elena A. Belanova, Pavel A. Kozlov, and Boris F. Myasoedov. "Valence and Local Environment of Molybdenum in Aluminophosphate Glasses for Immobilization of High Level Waste from Uranium-Graphite Reactor Spent Nuclear Fuel Reprocessing." MRS Proceedings 1744 (2015): 73–78. http://dx.doi.org/10.1557/opl.2015.299.

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ABSTRACTTwo Mo-bearing glasses considered as candidate forms for high level waste (HLW) a uranium-graphite reactor spent nuclear fuel (SNF) reprocessing were characterized. Incorporation of Mo in sodium aluminophosphate (SAP) glass increases its tendency to devitrification with segregation of orthophosphate phases. Valence state and local environment of Mo in the materials containing ∼2 wt.% MoO3 were determined by X-ray absorption fine structure (XAFS) spectroscopy. In the quenched samples composed of major vitreous and minor AlPO4 nearly all Mo is located in the vitreous phase as [Mo6+О6] units whereas in the annealed samples Mo is partitioned among vitreous and one or two orthophosphate crystalline phases in favor of the vitreous phase. Mo predominantly exists in a hexavalent state in distorted octahedral environment. Four oxygen ions are positioned at a distance of ∼1.71-1.73 Å and two - at a distance of 2.02-2.04 Å. Minor Mo(V) is also present as indicated by a response in EPR spectra with g ≈ 1.911-1.915.

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Berry, David Eric, Kathryn Anne Beveridge, Jane Browning, Gordon William Bushnell, and Keith Roger Dixon. "Ligand properties of phosphinito platinum complexes: 31P and 195Pt nuclear magnetic resonance studies and the crystal and molecular structure of [Cl(Et3P)Pt(μ-PPh2O)2Pt(PEt3)2][BF4]." Canadian Journal of Chemistry 64, no. 9 (September 1, 1986): 1903–11. http://dx.doi.org/10.1139/v86-314.

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Reaction of sodium hydride in tetrahydrofuran with the hydrogen-bonded phosphinito complex, [PtCl(PEt3){(PPh2O)2H}], gives a solution of the salt, [PtCl(PEt3){(PPh2O)2Na}], which is a precusor to synthesis of other bimetallic derivatives, [PtCl(PEt3){(μ-PPh2O)2Q}]n+: n = 0, Q = Rh(COD) or Ir(COD); n = 1, Q = Pd(PEt3)2 or Pt(PEt3)2. Detailed 31P and 195Pt nmr studies are reported for these and related examples including a titanium complex (n = 0, Q = Ti(acac)Cl2) synthesised by direct reaction of [PtCl(PEt3){(PPh2O)2H}] with [TiCl2(acac)2]. The diplatinurn complex, [Cl(PEt3)Pt(μ-PPh2O)2Pt(PEt3)2][BF4] crystallizes in the monoclinic space group P21/n, with a = 13.018(2), b = 34.205(9), c = 11.279(2) Å, β = 91.71(2)°. A complete X-ray diffraction study shows that the two platinum centres are significantly non-planar and are linked by the phosphinito ligands to form a six-membered ring in a boat conformation with phosphorus and oxygen atoms forming the prows of the boat.

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8

Caurant, Daniel, Arnaud Quintas, Odile Majérus, Thibault Charpentier, and I. Bardez. "Structural Role and Distribution of Alkali and Alkaline-Earth Cations in Rare Earth-Rich Aluminoborosilicate Glasses." Advanced Materials Research 39-40 (April 2008): 19–24. http://dx.doi.org/10.4028/www.scientific.net/amr.39-40.19.

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The structure of a seven oxide aluminoborosilicate simplified nuclear glass, bearing a high amount of neodymium or lanthanum oxide (16 wt%), alkali and alkaline earth cations is studied. Nd3+ or La3+ are supposed to simulate the trivalent lanthanides and minor actinides present in nuclear wastes. In the studied glass composition, lanthanide ions have a modifying role and are located in highly depolymerized regions of the structure as shown by neodymium optical absorption and EXAFS spectroscopies. Both alkali and alkaline earth cations are present around Nd3+ ions enabling their stabilization in glass structure near non-bridging oxygen atoms (NBOs). We show that both the nature of alkali R+ and alkaline earth R'2+ cations and the K = [R'O]/([R2O]+[R'O]) ratio can greatly influence the structure of the aluminoborosilicate glass network. Three glass series were prepared for which: (i) K ratio was varied from 0 to 0.5 (Na+ and Ca2+ being respectively the only alkali and alkaline-earth cations), (ii) the nature of R+ cation was varied from Li+ to Cs+ (Ca2+ being the only alkaline earth cation and K = 0.3), (iii) the nature of R'2+ cation was varied from Mg2+ to Ba2+ (Na+ being the only alkali cation and K = 0.3). 27Al MAS NMR spectroscopy results show that (AlO4)- units are preferentially charge compensated by alkali cations rather than by alkaline-earth cations. Both R+ and R’2+ cations can compensate (BO4)- units. Nevertheless, whereas the proportion N4 of (BO4)- units increases with the size of R'2+ cations, the evolution of N4 with R+ cation size for glasses of the R series is not monotonous. The evolution of sodium ions distribution trough glass structure is followed by 23Na MAS NMR spectroscopy.

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9

Lee, Sung Keun, George D. Cody, Yingwei Fei, and Bjorn O. Mysen. "Oxygen-17 Nuclear Magnetic Resonance Study of the Structure of Mixed Cation Calcium−Sodium Silicate Glasses at High Pressure: Implications for Molecular Link to Element Partitioning between Silicate Liquids and Crystals." Journal of Physical Chemistry B 112, no. 37 (September 18, 2008): 11756–61. http://dx.doi.org/10.1021/jp804458e.

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10

Kappaun, Karine, Anne H. S. Martinelli, Valquiria Broll, Barbara Zambelli, Fernanda C. Lopes, Rodrigo Ligabue-Braun, Leonardo L. Fruttero, et al. "Soyuretox, an Intrinsically Disordered Polypeptide Derived from Soybean (Glycine Max) Ubiquitous Urease with Potential Use as a Biopesticide." International Journal of Molecular Sciences 20, no. 21 (October 30, 2019): 5401. http://dx.doi.org/10.3390/ijms20215401.

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Ureases from different biological sources display non-ureolytic properties that contribute to plant defense, in addition to their classical enzymatic urea hydrolysis. Antifungal and entomotoxic effects were demonstrated for Jaburetox, an intrinsically disordered polypeptide derived from jack bean (Canavalia ensiformis) urease. Here we describe the properties of Soyuretox, a polypeptide derived from soybean (Glycine max) ubiquitous urease. Soyuretox was fungitoxic to Candida albicans, leading to the production of reactive oxygen species. Soyuretox further induced aggregation of Rhodnius prolixus hemocytes, indicating an interference on the insect immune response. No relevant toxicity of Soyuretox to zebrafish larvae was observed. These data suggest the presence of antifungal and entomotoxic portions of the amino acid sequences encompassing both Soyuretox and Jaburetox, despite their small sequence identity. Nuclear Magnetic Resonance (NMR) and circular dichroism (CD) spectroscopic data revealed that Soyuretox, in analogy with Jaburetox, possesses an intrinsic and largely disordered nature. Some folding is observed upon interaction of Soyuretox with sodium dodecyl sulfate (SDS) micelles, taken here as models for membranes. This observation suggests the possibility for this protein to modify its secondary structure upon interaction with the cells of the affected organisms, leading to alterations of membrane integrity. Altogether, Soyuretox can be considered a promising biopesticide for use in plant protection.

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11

Stetsuk, Ye V., O. Ye Akimov, and A. V. Mischenko. "ROLE OF THE REACTIVE OXYGEN AND NITROGEN SPECIES IN THE DEVELOPMENT OF FIBROSIS IN THE TESTES OF RATS WITH PROLONGED CENTRAL DEPRIVATION OF TESTOSTERONE SYNTHESIS." Актуальні проблеми сучасної медицини: Вісник Української медичної стоматологічної академії 20, no. 2 (July 6, 2020): 175–81. http://dx.doi.org/10.31718/2077-1096.20.2.175.

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Prostate cancer is the second most common diagnosis in oncology and ranks the fifth among the causes of mortality in men around the world. 1,276,106 cases of newly diagnosed prostate cancer were recorded in 2018. Androgens play a large role in the development of prostate cancer. Elimination of androgens and blockade of their synthesis are key pathogenetic steps in the treatment of prostate cancer. Metabolic and morphological changes in the testes under prolonged central deprivation of testosterone synthesis are currently not well understood. The aim of this study was to establish the role of reactive oxygen and nitrogen species in the development of morphological changes in the testes of rats under prolonged central deprivation of testosterone synthesis. Materials and methods. The experiments were conducted on 20 sexually mature male Wistar rats. Animals were divided into 4 groups of 5 animals in each. The first group (control) received a subcutaneous injection of 0.9% sodium chloride for 180 days. The second group received a subcutaneous injection of diphereline (triptoreline) in a dose of 0.3 mg/kg of active agent for 30 days in order to simulate the central deprivation of testosterone synthesis. In the third group, diphereline was administered in a dose of 0.3 mg/kg of the active agent for 90 days. The fourth group received a subcutaneous injection of diphereline in a dose of 0.3 mg/kg of the active agent for 180 days. Small pieces of testes were fixed and enclosed in paraffin blocks; then 4-μm thick sections were made and stained with hematoxylin and eosin. Histological preparations were studied using an optical microscope with a digital microphotographic nozzle Olympus C 3040-ADU with programs adapted for these studies. The total activity of NO synthases (gNOS), the activity of the inducible isoform of NO synthase (iNOS) and constitutive isoforms (cNOS), as well as the production of superoxide anion radical (O2•-) were determined in 10% homogenate of testes. Results. Long-term central deprivation of testosterone synthesis leads to an increase in the interstitial space volume with the development of fibrotic changes in the testes on the 180th day of the experiment. The wall of seminiferous tubules was compacted, swollen, there were a large number of parietal macrophages from the outside compared to previous periods of the experiment. In the structure of some convoluted seminiferous tubules, first there was discompletion and disorientation, and then desquamation of spermatids. The number of spermatogonia type A and B decreased. Hypochromia and pycnosis were noted in the nuclei. The activities of gNOS and iNOS increased until the 90th day and decreased by 180th when compared with 90th day, remaining higher than the activities of the control group. Activity of cNOS was reduced in all experimental groups. O2•- production increased in all experimental groups. Conclusion: an increase in the production of nitric oxide by the inducible isoform of NO synthase leads to destructive changes in the testes of rats with the subsequent development of fibrotic changes on the 180th day of central deprivation of testosterone synthesis by enhancing the production of superoxide anion radical.

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12

Lyutostansky, Yu S. "Disturbance of the shell structure of neutron-rich nuclei in the oxygen-magnesium region." Bulletin of the Russian Academy of Sciences: Physics 73, no. 2 (February 2009): 176–79. http://dx.doi.org/10.3103/s1062873809020099.

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13

Krawczyk, Marta S., and Irena Majerz. "The Na—O bond in sodium fenamate." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 75, no. 5 (August 31, 2019): 766–74. http://dx.doi.org/10.1107/s2052520619009065.

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The one-dimensional polymeric structure of sodium diaquafenamate–water (1/1) was studied by X-ray diffraction. The sodium cation is coordinated to one oxygen atom of the carboxylate group and to four water oxygen atoms. To characterize the Na—O bonds, the quantum theory of atoms in molecules (QTAIM) and noncovalent interaction (NCI) approaches have been used. Both methods confirmed that the Na—O bonds are very weak, comparable with the weak N—H...O intramolecular hydrogen bond. The polymeric structure is stabilized by the interaction of the sodium cation with the surrounding water molecules.

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14

He, Mingfu, Kah Chun Lau, Xiaodi Ren, Neng Xiao, William D. McCulloch, Larry A. Curtiss, and Yiying Wu. "Concentrated Electrolyte for the Sodium-Oxygen Battery: Solvation Structure and Improved Cycle Life." Angewandte Chemie 128, no. 49 (November 3, 2016): 15536–40. http://dx.doi.org/10.1002/ange.201608607.

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15

He, Mingfu, Kah Chun Lau, Xiaodi Ren, Neng Xiao, William D. McCulloch, Larry A. Curtiss, and Yiying Wu. "Concentrated Electrolyte for the Sodium-Oxygen Battery: Solvation Structure and Improved Cycle Life." Angewandte Chemie International Edition 55, no. 49 (November 3, 2016): 15310–14. http://dx.doi.org/10.1002/anie.201608607.

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16

Ha, N. T. T., N. V. Hong, and P. K. Hung. "Distribution of sodium and dynamical heterogeneity in sodium silicate liquid." International Journal of Modern Physics B 33, no. 05 (February 20, 2019): 1950013. http://dx.doi.org/10.1142/s0217979219500139.

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The structural and dynamical properties in sodium silicate liquid were investigated by molecular dynamics method. To clarify the distribution of sodium atoms in model, characteristics of simplex have been investigated. The simulation results reveal that Na2O⋅4SiO2 (NS4) liquid has a lot of simplexes with four sodium atoms inside but about half of simplexes do not have sodium. The spatial distribution of sodium is nonuniform, sodium tends to be in the nonbridging oxygen-simplexes and in larger-radius simplex. Moreover, the sodium density for nonbridging oxygen region is significantly higher than the one for Si-region. Namely, link-cluster function F[Formula: see text](r, t) has been used to clarify dynamical heterogeneity in NS4 liquid. The F[Formula: see text](r, t) for sets of random, immobile and mobile network atoms is quite different, which indicates that the dynamics of network atoms is heterogeneous. The Si–O network has the structure with two separated domains (immobile and mobile domains). These types of domain are significantly different in local microstructure, mobility of atoms and chemical composition.

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17

Kaduk, James A., Amy M. Gindhart, and Thomas N. Blanton. "Crystal structure of cloxacillin sodium monohydrate, C19H17ClN3O5SNa(H2O)." Powder Diffraction 34, no. 4 (September 2, 2019): 374–78. http://dx.doi.org/10.1017/s0885715619000678.

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The crystal structure of cloxacillin sodium monohydrate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Cloxacillin sodium monohydrate crystallizes in space group P212121 (#19) with a = 7.989 36(12), b = 10.918 09(10), c = 25.559 3(6) Å, V = 2229.50(5) Å3, and Z = 4. The crystal structure is characterized by corner-sharing chains of irregular NaO5 polyhedra along the a-axis. The carboxylate group chelates to the Na and bridges two Na cations. The coordination sphere is completed by the water molecule and a carbonyl group. The Na–O bonds are mostly ionic but have some covalent character. The bond valence sum of the Na is 1.14. The water molecule acts as a donor to the carboxylate group and a carbonyl oxygen. It is an acceptor in C–H⋯O hydrogen bonds from a methyl group and a ring carbon. The crystal structure of cloxacillin sodium monohydrate is very similar to that of the fluorinated derivative (CSD Refcode BEBCAM), reflecting the similarity of the lattice parameters. The powder pattern has been submitted to ICDD for inclusion in the Powder Diffraction File™.

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18

Pal, M. "Structure and physical properties of sodium antimony germanate glasses." Journal of Materials Research 11, no. 7 (July 1996): 1831–35. http://dx.doi.org/10.1557/jmr.1996.0231.

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The structure and physical properties of sodium antimony germanate glasses with compositions 10Na2O − xSb2O3 − (90 − x)GeO2, x = 10−30 mol%, prepared by the melt-quenched route have been studied. It is observed from x-ray diffraction, SEM, density and oxygen molar volume, infrared (IR), differential thermal analysis (DTA), and optical absorption that single phase homogeneous glasses with a random network structure can be obtained in this system. The strength and connectivity of the glass network increase with GeO2 content. The main Ge−O stretching vibration also shifts to higher wavelength side. Two oxidation states of antimony, Sb3+ and Sb5+, are present, while the so-called “germanate anomaly” is absent in these glasses. This study discusses the probable structural reasons behind this type of behavior of these glasses.

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19

Olimov, Kosim, Khusniddin K. Olimov, Sagdulla L. Lutpullaev, Erkin Kh Bazarov, Alisher K. Olimov, Vladimir V. Lugovoi, K. G. Gulamov, and Vadim Sh Navotny. "Breakup of 16O nucleus onto C and He isotopes by protons at incident momentum of 3.25AGeV/c." International Journal of Modern Physics E 25, no. 03 (March 2016): 1650023. http://dx.doi.org/10.1142/s0218301316500233.

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Phenomenological analysis of breakup of oxygen nuclei on fragments with charges two and six in collisions with protons at [Formula: see text][Formula: see text]GeV/[Formula: see text] was conducted using the Monte Carlo (MC) model of isotropic phase space. For the first time, the contributions of mechanism of diffractive breakup of oxygen nucleus, and that of quasi elastic knocking out of one of the [Formula: see text] clusters of oxygen nucleus by a proton target, into channel of formation of [Formula: see text] particle and [Formula: see text]C nucleus with conservation of recoil proton were determined in final state. The substantial role of [Formula: see text] cluster structure of initial nucleus in processes of fragmentation of oxygen nuclei in peripheral interactions with protons was revealed in experiment.

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20

Haines, Alan H., and David L. Hughes. "Crystal structure of sodium (1S)-D-lyxit-1-ylsulfonate." Acta Crystallographica Section E Crystallographic Communications 72, no. 5 (April 5, 2016): 628–31. http://dx.doi.org/10.1107/s2056989016005375.

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The title compound, Na+·C5H11O8S−[systematic name: sodium (1S,2S,3S,4R)-1,2,3,4,5-pentahydroxypentane-1-sulfonate], is formed by reaction of D-lyxose with sodium bisulfite (sodium hydrogen sulfite) in water. The anion has an open-chain structure in which one of the oxygen atoms of the sulfonate residue, the S atom, the C atoms of the sugar chain and the O atom of the hydroxymethyl group form an essentially planar zigzag chain with the corresponding torsion angles lying between 179.80 (11) and 167.74 (14)°. A three-dimensional bonding network exists in the crystal structure involving hexacoordination of sodium ions by O atoms, three of which are provided by a single D-lyxose–sulfonate unit and the other three by two sulfonate groups and one hydroxymethyl group, each from separate units of the adduct. Extensive intermolecular O—H...O hydrogen bonding supplements this bonding network.

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Baster, Dominika, Krzysztof Dybko, Michał Szot, Konrad Świerczek, and Janina Molenda. "Sodium intercalation in Na CoO2− — Correlation between crystal structure, oxygen nonstoichiometry and electrochemical properties." Solid State Ionics 262 (September 2014): 206–10. http://dx.doi.org/10.1016/j.ssi.2013.11.040.

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22

Guesmi, Abderrahmen, Massimo Nespolo, and Ahmed Driss. "Synthesis, crystal structure and charge distribution of Na7As11O31: An oxygen-deficient layered sodium arsenate." Journal of Solid State Chemistry 179, no. 8 (August 2006): 2466–71. http://dx.doi.org/10.1016/j.jssc.2006.04.010.

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23

Calhorda, Maria Jose, and Roald Hoffmann. "Dimensionality and metal-metal and metal-oxygen bonding in the sodium niobate (NaNb3O6) structure." Journal of the American Chemical Society 110, no. 25 (December 1988): 8376–85. http://dx.doi.org/10.1021/ja00233a015.

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Yuan, Cenxi. "Systematic shell-model study on spectroscopic properties from light to heavy nuclei." EPJ Web of Conferences 178 (2018): 02016. http://dx.doi.org/10.1051/epjconf/201817802016.

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A systematic shell-model study is performed to study the spectroscopic properties from light to heavy nuclei, such as binding energies, energy levels, electromagnetic properties, and β decays. The importance of cross-shell excitation is shown in the spectroscopic properties of neutron-rich boron, carbon, nitrogen, and oxygen isotopes. A special case is presented for low-lying structure of 14C. The weakly bound effect of proton 1s1/2 orbit is necessary for the description of the mirror energy difference in the nuclei around A=20. Some possible isomers are predicted in the nuclei in the southeast region of 132Sn based on a newly suggested Hamiltonian. A preliminary study on the nuclei around 208Pb are given to show the ability of the shell model in the heavy nuclei.

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Plane, J. M. C. "The role of sodium bicarbonate in the nucleation of noctilucent clouds." Annales Geophysicae 18, no. 7 (July 31, 2000): 807–14. http://dx.doi.org/10.1007/s00585-000-0807-2.

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Abstract. It is proposed that a component of meteoric smoke, sodium bicarbonate (NaHCO3), provides particularly effective condensation nuclei for noctilucent clouds. This assertion is based on three conditions being met. The first is that NaHCO3 is present at sufficient concentration (±104 cm-3) in the upper mesosphere between 80 and 90 km. It is demonstrated that there is strong evidence for this based on recent laboratory measurements coupled with atmospheric modelling. The second condition is that the thermodynamics of NaHCO3(H2O)n cluster formation allow spontaneous nucleation to occur under mesospheric conditions at temperatures below 140 K. The Gibbs free energy changes for forming clusters with n = 1 and 2 were computed from quantum calculations using hybrid density functional/Hartree-Fock (B3LYP) theory and a large basis set with added polarization and diffuse functions. The results were then extrapolated to higher n using an established dependence of the free energy on cluster size and the free energy for the sublimation of H2O to bulk ice. A 1-dimensional model of sodium chemistry was then employed to show that spontaneous nucleation to form ice particles (n >100) should occur between 84 and 89 km in the high-latitude summer mesosphere. The third condition is that other metallic components of meteoric smoke are less effective condensation nuclei, so that the total number of potential nuclei is small relative to the amount of available H2O. Quantum calculations indicate that this is probably the case for major constituents such as Fe(OH)2, FeO3 and MgCO3.Key words: Atmospheric composition and structure (aerosols and particles; cloud physics and chemistry; middle atmosphere · composition and chemistry)

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26

Loub, Josef, Zdeněk Mička, Jana Podlahová, Karel Malý, and Jürgen Kopf. "Structure of Sodium Hydrogen Selenite-Selenious Acid Adduct (1:3), NaHSeO3.3H2SeO3." Collection of Czechoslovak Chemical Communications 57, no. 11 (1992): 2309–14. http://dx.doi.org/10.1135/cccc19922309.

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Structure of sodium hydrogen selenite-selenious acid (1:3) was solved by heavy-atom method and refined anisotropically to R = 0.098 for 1223 unique observed reflections. The title compound crystallizes in the Pc space group with a = 5.756(2), b = 4.911(2), c = 20.010(5) Å, β = 100.48(3)°, V = 556(1) Å3, T = 293 K, (a = 5.763(2), b = 4.878(1), c = 20.03(1) Å, β = 100.48(3)°, V = 554(1) Å3, T = 173 K), Z = 2. The structure consist of HSeO3- anions, molecules of selenious acid and Na+ cations which are octahedrally coordinated with oxygen atoms. The structure is stabilized by a system of hydrogen bonds.

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27

Tirkkonen, B., A. Aukrust, E. Couture, D. Grace, Y. Haile, K. M. Holm, H. Hope, Å. Larsen, H. Sivertsen Lunde, and C. E. Sjøgren. "Physicochemical characterisation of mangafodipir trisodium." Acta Radiologica 38, no. 5 (September 1997): 780–89. http://dx.doi.org/10.1080/02841859709172411.

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Purpose: To determine the structure and various physicochemical properties of man-gafodipir (MnDPDP) trisodium, the active ingredient of Teslascan, a new organ-specific contrast medium for MR imaging. Material and Methods: The structure of MnDPDP trisodium crystals was determined by X-ray crystallography. The possible existence of polymorphism in MnDPDP trisodium was evaluated by powder X-ray diffraction, optical microscopy, thermal analysis and IR spectroscopy. In addition, various spectroscopic techniques and physicochemical measurements were used for characterisation of MnDPDP trisodium. Results: The crystallographic data obtained for MnDPDP trisodium show that the general core structure of the MnDPDP anion is similar to that seen in related substances. The metal coordination geometry is a distorted octahedron defined by 2 phenolate oxygens, 2 carboxylate oxygens and 2 amine nitrogens. The unit cell contains 2 MnDPDP anions, 6 sodium ions and 50 water molecules. The various spectroscopic data are consistent with the structure determined by X-ray crystallography. The product (Teslascan) has low viscosity, is isotonic with blood and has a physiological pH. Conclusion: MnDPDP trisodium is a crystalline, hygroscopic solid which is readily soluble in water. No evidence of polymorphism was seen in the samples studied.

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28

Runciman, WA, B. Srinivasan, and S. Saebo. "Electronic Structure of the Principal Uranium Centre in Alkali Fluorides." Australian Journal of Physics 39, no. 4 (1986): 555. http://dx.doi.org/10.1071/ph860555.

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Fluorescent centres are formed when hexavalent uranium is incorporated into lithium fluoride and sodium fluoride in an oxygen atmosphere. The principal centre is believed to consist of a UOsF group. Calculations have been made of the electronic structure of this centre assuming that the excited states are due to charge transfer transitions. Different models are considered and fitting procedures used to find parameters yielding good agreement with the energy levels and 9 values of the seven lowest excited states of the centre in sodium fluoride. A similar model is believed to be applicable to the principal centre in lithium fluoride.

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29

Siidra, Oleg I., Evgeny V. Nazarchuk, Dmitry O. Charkin, Nikita V. Chukanov, Alexander Yu Zakharov, Stepan N. Kalmykov, Yuriy A. Ikhalaynen, and Mikhail I. Sharikov. "Open-framework sodium uranyl selenate and sodium uranyl sulfate with protonated morpholino-N-acetic acid." Zeitschrift für Kristallographie - Crystalline Materials 234, no. 2 (February 25, 2019): 109–18. http://dx.doi.org/10.1515/zkri-2018-2103.

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Abstract The reaction of sodium N-morpholine acetate with selenic and sulfuric acid and uranyl nitrate results in the formation of two novel open-framework compounds, |Na(Hmfa)|[(UO2)2(SeO4)3(H2O)](H2O)2 (NaUSe) and [Na2(SO3OH)(Hmfa)]|(UO2)(SO4)2| (NaUS), respectively. Despite identical synthetic procedures, sulfate structure dramatically differs from selenate compound. Their common feature is an open-framework featuring two-dimensional system of channels occupied by protonated morpholino-N-acetic acid species. Coordination of Na atoms is different. In NaUSe, [(UO2)2 (SeO4)3(H2O)]2− layers are pillared by {Na2O8(H2O)2(Hmfa)2} complexes to form a microporous framework. In NaUS, UO7 and SO4 polyhedra of [(UO2)(SO4)2]2− chains share common oxygen atoms with Na-centered tetrameric complexes providing a three-dimensional integrity of the structure. Both of the compounds are characterized by IR spectroscopy.

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30

Gonzalez, Diana, Joseph T. Golab, James A. Kaduk, Amy M. Gindhart, and Thomas N. Blanton. "Crystal structure of pantoprazole sodium sesquihydrate Form I, C16H14F2N3O4SNa(H2O)1.5." Powder Diffraction 35, no. 1 (January 20, 2020): 53–60. http://dx.doi.org/10.1017/s0885715620000019.

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The crystal structure of pantoprazole sodium sesquihydrate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Pantoprazole sodium sesquihydrate crystallizes in space group Pbca (#61) with a = 33.4862(6), b = 17.29311(10), c = 13.55953(10) Å, V = 7852.06(14) Å3, and Z = 16. The crystal structure is characterized by layers parallel to the bc-plane. One layer contains the Na coordination spheres. The two independent sodium ions are trigonal bipyramidal and octahedral. The NaO3N2 and NaO4N2 coordination spheres share an edge to form pairs. The sodium bond valence sums are 1.17 and 1.15. The difluoromethyl groups are probably disordered. Two water molecules act as hydrogen bond donors to pyridine nitrogen atoms and sulfoxide oxygen atoms. The third water molecule participates in bifurcated hydrogen bonds, but one of its hydrogen atoms does not participate in hydrogen bonds. The powder pattern is included in the Powder Diffraction File™ as entry 00-065-1424.

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31

Litton, David A., and Stephen H. Garofalini. "Atomistic Structure of Sodium and Calcium Silicate Intergranular Films in Alumina." Journal of Materials Research 14, no. 4 (April 1999): 1418–29. http://dx.doi.org/10.1557/jmr.1999.0192.

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Sodium silicate intergranular films (IGF) in contact with the [0001] basal plane of α-alumina were studied using the molecular dynamics computer simulation technique. The results were compared to previous simulations of calcium silicate and sol-gel silica IGF's in contact with alumina. An ordered, cagelike structure was observed at the interface. Sodium ions segregated to the cages at the interfaces. Calcium and hydrogen ions were also observed to segregate to the cages in the previous simulations. The modifier ions were surrounded by more oxygen ions in the cages at the interface than in the bulk of the IGF. This explains the segregation of modifiers at the interface. Interface energy decreased as the sodium content of the IGF increased. Interface energy decreased faster as a function of Na2O content than as a function of CaO content. However, interface energy decreased slower as a function of Na+ content than as a function of Ca2+content.

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32

Shtokvysh, O., L. Koval, V. Dyakonenko, and V. Pekhnyo. "STRUCTURE OF THE ZINC COMPLEX WITH CYCLOHEXYL AСETOACETATE." Bulletin of Taras Shevchenko National University of Kyiv. Chemistry, no. 1 (57) (2020): 66–69. http://dx.doi.org/10.17721/1728-2209.2020.1(57).16.

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Binuclear complex of Zn(II) with cyclohexyl acetoacetate was obtained and structurally characterized for the first time. According to structural data, the crystal system is triclinic, space group P-1; a = 7.6530(4), b = 12.2412(8), c = 12.9102(9) Å; α = 90.198(5), β = 101.071(5), γ = 96.937(5) deg. The molecular structure corresponds to the formula [Zn2(C10H15O3)4(C2H5OH)2]. The complex is located in a special position to the symmetry center of the unit cell. The coordination polyhedrons of the Zn atoms are the same distorted octahedrons formed by six oxygen atoms. Each formed by 4 oxygen atoms in the equatorial position, which belong to three ligand molecules: terminal ligand (2 oxygen atoms) and bridged ligand (1 oxygen atom) which chelate the zinc atom of the named polyhedron and 1 oxygen atom belong to a bridged ligand that chelates the other nucleus and monodentantly coordinated to mentioned one. Two oxygen atoms occupy an axial position, one of which belongs to the terminal ligand, mentioned above and the other to the coordinated ethanol molecule. The bond between the complex nuclei is stabilized by two hydrogen bonds formed by the hydrogen atoms from hydroxyl groups of ethanol molecules and the enol oxygen atoms of the terminal ligands of the other nucleus. The compound was also characterized by IR-spectroscopy, characteristic bands (сm-1) are: ν(C–H) - 2936, 2860, ν(C=O) & ν(C=C) – 1612, ν(C=O) + δ(C–H) – 1532, ν(C=C) & ν(C-CH3)– 1252, δ(C–H) – 1172, π(C–H) – 784, ν(M–O) – 456, 416. IR spectroscopy data confirm the bidentate coordination of cyclohexyl acetoacetate to zinc atoms in deprotonated form with the formation of chelated metallocycles. The structure of the complex is similar to the structures of cobalt and nickel complexes with cyclohexyl acetoacetate. Analysis of XRD-data (which are supplemented with this work) for Co(II), Ni(II) and Zn(II) complexes with acetoacetic acid esters shows that their structure, in particular the number of metal centers in the structures, regardless of the nature of the central atom or the alcohol fragment, but determined the presence of components capable of complementing the coordination sphere of the metal in reaction media.

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33

Müller, Kerstin, Klaus-Jürgen Range, and Anton M. Heyns. "Alkalimetallformiate, V Die Kristallstruktur von Natriumformiat-Dihydrat, NaHCO2·2H2O [1] Alkali Metal Formates, V The Crystal Structure of Sodium Formate Dihydrate, NaHCO2·2H2O [1]." Zeitschrift für Naturforschung B 49, no. 9 (September 1, 1994): 1179–82. http://dx.doi.org/10.1515/znb-1994-0905.

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Single crystals of sodium formate dihydrate, NaHCO2·2H2O, have been prepared from aqueous solutions of sodium formate, NaHCO2, via the trihydrate, NaHCO2-3H2O. They are orthorhombic, space group Cmca, with a = 7.070(4), b = 14.534(2), c = 8.706(2) Å and Z = 8. The structure, including the hydrogen atoms, was refined to R = 0.054, Rw = 0.065 for 479 unique reflections with I > 3 σ (I). It comprises buckled layers formed by NaO6 octahedra which are edge- and corner-sharing. The octahedral coordination of the sodium ions is achieved by two oxygen atoms from two different end-on bonded formate ions and four water oxygen atoms. The O···H distances show clearly that strong hydrogen bonds are not involved in the bonding system

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34

Sharma, Himanshu, and Divya S. Sharma. "Detection of Hydroxyl and Perhydroxyl Radical Generation from Bleaching Agents with Nuclear Magnetic Resonance Spectroscopy." Journal of Clinical Pediatric Dentistry 41, no. 2 (January 1, 2017): 126–34. http://dx.doi.org/10.17796/1053-4628-41.2.126.

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Objective: Children/adolescent's orodental structures are different in anatomy and physiology from that of adults, therefore require special attention for bleaching with oxidative materials. Hydroxyl radical (OH.) generation from bleaching agents has been considered directly related to both its clinical efficacy and hazardous effect on orodental structures. Nonetheless bleaching agents, indirectly releasing hydrogen peroxide (H2O2), are considered safer yet clinically efficient. Apart from OH., perhydroxyl radicals (HO2.) too, were detected in bleaching chemistry but not yet in dentistry. Therefore, the study aims to detect the OH. and HO2. from bleaching agents with their relative integral value (RIV) using 31P nuclear magnetic resonance (31PNMR) spectroscope. Study design: Radicals were generated with UV light in 30% H2O2, 35% carbamide peroxide (CP), sodium perborate tetrahydrate (SPT) and; neutral and alkaline 30% H2O2. Radicals were spin-trapped with DIPPMPO in NMR tubes for each test agents as a function of time (0, 1, 2, 3min) at their original pH. Peaks were detected for OH. and HO2. on NMR spectrograph. RIV were read and compared for individual radicals detected. Results: Only OH. were detected from acidic and neutral bleaching agent (30% acidic and neutral H2O2, 35%CP); both HO2. and OH. from 30% alkaline H2O2; while only HO2. from more alkaline SPT. RIV for OH. was maximum at 1min irradiation of acidic 30%H2O2 and 35%CP and minimum at 1min irradiation of neutral 30%H2O2. RIV for HO2.was maximum at 0min irradiation of alkaline 30%H2O2 and minimum at 2min irradiation of SPT. Conclusion: The bleaching agents having pH- neutral and acidic were always associated with OH.; weak alkaline with both OH. and HO2.; and strong alkaline with HO2. only. It is recommended to check the pH of the bleaching agents and if found acidic, should be made alkaline to minimize oxidative damage to enamel itself and then to pulp/periodontal tissues. Abbreviations: H2O2: hydrogen peroxide CP: carbamide peroxide SP: sodium perborate SPT: sodium perborate tetrahydrate ROS: reactive oxygen species 31PNMR: 31P nuclear magnetic resonance spectroscope RIV: relative integral value OH2.: hydroxyl radical HO2 .: perhydroxyl radical O2 .: super oxide radical DIPPMPO: 5-(Diisopropoxyphosphoryl)-5-methyl-1-pyrroline-N-oxide DEPMPO: 5-diethoxyphosphoryl-5-methyl-1-pyrroline-n-oxide DMPO: 5,5-dimethyl-1-pyrroline-N-oxide D2O: heavy water EDTA: ethylene diamine tetra acetic acid

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35

Bott, RC, DS Sagatys, DE Lynch, G. Smith, and CHL Kennard. "The Preparation and Crystal Structure of Polymeric Anhydrous Sodium Hydrogen o-Phenylenedioxydiacetate." Australian Journal of Chemistry 45, no. 5 (1992): 947. http://dx.doi.org/10.1071/ch9920947.

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The crystal structure of anhydrous sodium hydrogen o-phenylenedioxydiacetate , [Na2( Hbdda )2]n, has been determined by X-ray methods and refined to a residual R 0.031 for 1234 observed reflections. Crystals are monoclinic, space group C2/c with Z 4 in a cell of dimensions a 18.415(6), b 7.4667(7), c 16.354(7) � ,β112.61(2)�. The dimeric repeating unit has two centrosymmetrically related pentagonal pyramidal Na-O6 complex centres [Na-0, 2.272-2.439(2) � ] bridged by carboxylate oxygens. The pentagonal plane comprises four oxygens from the Hbdda ligand as well as one providing the bridging link. The axial bond gives the step-polymer link while the carboxylic acid proton is hydrogen bonded to a carboxylate oxygen of the inversion-related Hbdda ligand [O…O, 2.469(2) � ].

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36

Shcherbakova, Irina V., Evghenii V. Kuznetsov, Iosif A. Yudilevich, Olga E. Kompan, Alexandru T. Balaban, Aleksei H. Abolin, Alexander V. Polyakov, and Yurii T. Struchkov. "2-benzopyrylium salts. XXXVII. Oxygen analogs of reissert compounds : molecular structure and reactions with sodium hydroxide." Tetrahedron 44, no. 19 (January 1988): 6217–24. http://dx.doi.org/10.1016/s0040-4020(01)89812-4.

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37

Klaeui, W., A. Mueller, W. Eberspach, R. Boese, and I. Goldberg. "Crystal structure and coordination chemistry of the pentane-soluble sodium salt of an oxygen tripod ligand." Journal of the American Chemical Society 109, no. 1 (January 1987): 164–69. http://dx.doi.org/10.1021/ja00235a025.

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38

Olimov, Kosim, Sagdulla L. Lutpullaev, Khusniddin K. Olimov, Alisher K. Olimov, Vladimir I. Petrov, Viktor V. Glagolev, and B. S. Yuldashev. "Some peculiarities of formation of 4He nuclei in 16Op collisions at 3.25A GeV/c." International Journal of Modern Physics E 23, no. 12 (December 2014): 1450086. http://dx.doi.org/10.1142/s0218301314500864.

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The new experimental data on dependences of the mean multiplicities and kinematical characteristics of 4 He nuclei, formed in 16 O p collisions at 3.25A GeV/c, on degree of excitation of the fragmenting nucleus are presented. It is shown that the initial (α cluster) structure of oxygen nucleus is retained at small excitation levels. It is established that the kinematical characteristics of 1 H , 2 H , 3 H and 3 He fragments do not depend on availability or absence of α particles in a collision event, which indicates the independence of mechanisms of formation of such fragments and 4 He nuclei.

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39

Gamag, e., e. Gamag, BM Peake, BM Peake, J. Simpson, and J. Simpson. "X-Ray Crystal Structure Determination of Some Sodium Anthraquinone Sulfonate Derivatives." Australian Journal of Chemistry 46, no. 10 (1993): 1595. http://dx.doi.org/10.1071/ch9931595.

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The crystal structures of sodium 9,10-dioxo-9,10-dihydroanthracene-2-sulfonate hydrate (1) and sodium 9,10-dioxo-9,10-dihydroanthracene-1,5-disulfonate trihydrate (2) have been determined by single-crystal X-ray diffraction at 253 K and refined to R 0.03 for (1) (1535 reflections) and R 0.04 for (2) (1409 reflections). Crystals of (1) are monoclinic, P21, a 17.395(5), b 6.625(2), c 5.537(1)Ǻ, β 91.87(2)°, Z 2, and those of (2) are orthorhombic, Pnma, a 11.332(4), b 20.048(5), c 7.634(3)Ǻ, Z 4. The results of molecular mechanics calculations on these two molecules were in general agreement with those determined by X-ray methods. The effect of sulfonate substitution in the 1-position compared with that in the 2-position include a small lengthening of the C-S bond and a displacement of the sulfur and quinone oxygen atoms to opposite sides of the plane of the substituted aromatic ring. However, these differences do not appear to be of sufficient magnitude to account for the much greater differences in the electrochemical and photochemical behaviour of these two classes of anthraquinone sulfonate derivatives.

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40

Benhsina, Elhassan, Jamal Khmiyas, Said Ouaatta, Abderrazzak Assani, Mohamed Saadi, and Lahcen El Ammari. "Synthesis and crystal structure of NaCuIn(PO4)2." Acta Crystallographica Section E Crystallographic Communications 76, no. 3 (February 14, 2020): 366–69. http://dx.doi.org/10.1107/s2056989020001929.

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Single crystals of sodium copper(II) indium bis[phosphate(V)], NaCuIn(PO4)2, were grown from the melt under atmospheric conditions. The title phosphate crystallizes in the space group P21/n and is isotypic with KCuFe(PO4)2. In the crystal, two [CuO5] trigonal bipyramids share an edge to form a dimer [Cu2O8] that is connected to two PO4 tetrahedra. The obtained [Cu2P2O12] units are interconnected through vertices to form sheets that are sandwiched between undulating layers resulting from the junction of PO4 tetrahedra and [InO6] octahedra. The two types of layers are alternately stacked along [101] and are joined into a three-dimensional framework through vertex- and edge-sharing, leaving channels parallel to the stacking direction. The channels host the sodium cations that are surrounded by four oxygen atoms in form of a distorted disphenoid.

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41

Korus, Gabriele, and Martin Jansen. "Untersuchungen An Natriumtrifluormethylsulfonat. Kristallstruktur von Natriumtrifluormethylsulfonat- Trifluormethylsulfonsäure (1/3) / Studies on Sodium Trifluoromethanesulfonate. Crystal Structure of Sodium Trifluoromethanesulfonate-Trifluoromethanesulfonic Acid (1/3)." Zeitschrift für Naturforschung B 53, no. 4 (April 1, 1998): 438–42. http://dx.doi.org/10.1515/znb-1998-0409.

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Abstract Single crystals of sodium trifluoromethanesulfonate-trifluoromethanesulfonic acid (1/3) (NaSO3CF3 · 3 HSO3CF3) have been prepared by reaction of sodium trifluoromethanesulfonate with anhydrous trifluoromethanesulfonic acid at 60 °C. NaSO3CF3 · 3 HSO3CF3 crystallizes in space group I213 (No. 199) with a = 16.210(1) Å, Z = 8. Sodium is coordinated by six oxygen atoms from six different trifluoromethanesulfonic acid molecules, each acid molecule connecting two sodium ions. The 3-dimensional network resulting from the edge sharing octahedra corresponds to the cubic (10, 3) net, not realised otherwise, so far. The trifluoromethanesulfonate anion is bonded to three trifluoromethanesulfonic acid molecules by hydrogen bonds.

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42

Gowda, Basavalinganadoddy Thimme, Sabine Foro, Jozef Kožíšek, and Hartmut Fuess. "Crystal Structure Studies on Arylsulphonamides and N-Chloro-Arylsulphonamides." Zeitschrift für Naturforschung A 62, no. 7-8 (August 1, 2007): 417–24. http://dx.doi.org/10.1515/zna-2007-7-811.

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The effect of ring substitution and N-chlorination on the molecular geometry of arylsulphonamides and N-chloro-arylsulphonamides have been studied by determining the crystal structures of 2-methyl- 4-chloro-benzenesulphonamide (2M4CBSA) and the sodium salt of N-chloro-2-methyl-4-chlorobenzenesulphonamide (NaNC2M4CBSA). The results are analyzed along with the crystal structures of benzenesulphonamide, 4-methyl-benzenesulphonamide and 4-chloro-benzenesulphonamide. The crystal structure of NaNC2M4CBSA has also been compared and correlated with the crystal structures of the above compounds and those of the sodium salts of N-chloro-benzenesulphonamide, Nchloro- 4-methyl-benzenesulphonamide, N-chloro-4-chloro-benzenesulphonamide and N-chloro-2,4- dichloro-benzenesulphonamide. The crystal system, space group, formula units and lattice constants in Å of the new structures are: 2M4CBSA: triclinic, P1, Z = 4, a = 7.9030(10), b = 8.6890(10), c = 13.272(2), α = 100.680(10)°, β = 98.500(10)°, γ = 90.050(10)°; NaNC2M4CBSA: monoclinic, C2/c, Z =4, a = 10.9690(10), b = 6.7384(6), c = 30.438(2), β = 98.442(7)°. The structure of 2M4CBSA is quite complex with four molecules in its asymmetric unit. The S-N bond length slightly decreases with substitution of electron-withdrawing groups, while the effect is more pronounced with disubstitution. The structure of NaNC2M4CBSA confirms that there is no interaction between nitrogen and sodium, and Na+ is attached to one of the sulphonyl oxygen atoms. The Na+ coordination sphere involves oxygen atoms from water moleculess of crystallization and neighbouring molecules. The S-N distance of 1.586 Å for the compound is consistent with a S-N double bond. The molecules are held together by hydrogen bonds with distances varying from 2.12 to 2.85 Å.

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43

Wang, Guangguo, Yongquan Zhou, He Lin, Zhuanfang Jing, Hongyan Liu, and Fayan Zhu. "Structure of aqueous sodium acetate solutions by X-Ray scattering and density functional theory." Pure and Applied Chemistry 92, no. 10 (October 25, 2020): 1627–41. http://dx.doi.org/10.1515/pac-2020-0402.

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AbstractThe structure of aq. sodium acetate solution (CH3COONa, NaOAc) was studied by X-ray scattering and density function theory (DFT). For the first hydrated layer of Na+, coordination number (CN) between Na+ and O(W, I) decreases from 5.02 ± 0.85 at 0.976 mol/L to 3.62 ± 1.21 at 4.453 mol/L. The hydration of carbonyl oxygen (OC) and hydroxyl oxygen (OOC) of CH3COO− were investigated separately and the OC shows a stronger hydration bonds comparing with OOC. With concentrations increasing, the hydration shell structures of CH3COO− are not affected by the presence of large number of ions, each CH3COO− group binds about 6.23 ± 2.01 to 7.35 ± 1.73 water molecules, which indicates a relatively strong interaction between CH3COO− and water molecules. The larger uncertainty of the CN of Na+ and OC(OOC) reflects the relative looseness of Na-OC and Na-OOC ion pairs in aq. NaOAc solutions, even at the highest concentration (4.453 mol/L), suggesting the lack of contact ion pair (CIP) formation. In aq. NaOAc solutions, the so called “structure breaking” property of Na+ and CH3COO− become effective only for the second hydration sphere of bulk water. The DFT calculations of CH3COONa (H2O)n=5–7 clusters suggest that the solvent-shared ion pair (SIP) structures appear at n = 6 and become dominant at n = 7, which is well consistent with the result from X-ray scattering.

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44

Kalinowska, M., W. Lewandowski, R. Swislocka, and E. Regulska. "The FT-IR, FT-Raman,1H and13C NMR study on molecular structure of sodium(I), calcium(II), lanthanum(III) and thorium(IV) cinnamates." Spectroscopy 24, no. 3-4 (2010): 277–81. http://dx.doi.org/10.1155/2010/679842.

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In this work the effect of sodium(I), calcium(II), lanthanum(III) and thorium(IV) ions on the electronic structure of cinnamic acid (phenylacrylic acid) was studied. In this research: infrared (FT-IR), Raman (FT-Raman), nuclear magnetic resonance (1H,13C NMR) were used. In the series of Na(I)→ Ca(II)→ La(III)→ Th(IV) cinnamates: (1) systematic shifts of several bands in the FT-IR and FT-Raman spectra, and (2) regular chemical shifts of protons1H and13C nuclei were observed.

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45

Tyutyunnik, Alexander P., Vladimir G. Zubkov, Ludmila L. Surat, Boris V. Slobodin, and Gunnar Svensson. "Synthesis and crystal structure of the pyrovanadate Na2ZnV2O7." Powder Diffraction 20, no. 3 (September 2005): 189–92. http://dx.doi.org/10.1154/1.1924434.

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The compound Na2ZnV2O7 with an åkermanite-type structure has been synthesized. It has a tetragonal unit cell, a=8.2711(4), c=5.1132(2) Å, and crystallizes with P-421m symmetry, Z=2. Its crystal structure has been refined from a combination of X-ray and neutron powder diffraction data. The structure contains layers of corner-sharing VO4 and ZnO4 tetrahedra, the former in pairs forming pyrovanadate V2O7 units. The sodium atoms are positioned between the layers, with a distorted antiprismatic coordination of oxygen atoms.

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46

Zhao, Wenqing, Limin Zhang, Feng Jiang, Xinghua Chang, Yue Yang, Peng Ge, Wei Sun, and Xiaobo Ji. "Engineering metal sulfides with hierarchical interfaces for advanced sodium-ion storage systems." Journal of Materials Chemistry A 8, no. 10 (2020): 5284–97. http://dx.doi.org/10.1039/c9ta13899d.

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Utilizing oxygen functional groups, interfacial reactions were carried out on the surface of natural stibnite, resulting in the formation of Sb₂S₃/Sb core–shell structure and sulfur-doped carbon matrix with improved sodium-storage capabilities.

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47

Cheng, Chien Min, Shih Fang Chen, Jen Hwan Tsai, Kai Huang Chen, and Hsiu Hsien Su. "Electrical and Physical Properties of Sodium Potassium Niobates Thin Films Prepared by rf Magnetron Sputtering Technology." Advanced Materials Research 239-242 (May 2011): 532–35. http://dx.doi.org/10.4028/www.scientific.net/amr.239-242.532.

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Lead-free potassium sodium niobate ceramic thin films were synthesized using rf magnetron sputtering technology for MFIS structures. The optimal sputtering parameters of the as-deposited KNN thin films for depositing times of 1h were obtained. Regarding the measured physical properties, the micro-structure and thickness of as-deposited KNN thin films for different oxygen concentration were obtained and compared by XRD patterns and SEM images. The surface roughness of KNN thin film was also observed by AFM morphology. The average grain size and root mean square roughness were 250 and 7.04 nm, respectively. For KNN thin films in the MFIS structure, the capacitance and leakage current density were 280 pF and 10-8A/cm2, respectively. We investigated that the leakage current density and the memory window increased, the capacitance critically increased as the oxygen concentration increased from 0 to 40%. However, the excess oxygen concentration process was decreased the electrical and physical of as-deposited KNN thin film. The effect of oxygen concentration on the physical and electrical characteristics of KNN thin films was investigated and determined.

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48

Ernst, Wolfgang E., and Stefan Rakowsky. "Rotational structure of the B–X system of Na3 from high-resolution resonant two-photon ionization spectroscopy." Canadian Journal of Physics 72, no. 11-12 (November 1, 1994): 1307–14. http://dx.doi.org/10.1139/p94-166.

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First investigations of the [Formula: see text] system of Na3 at rotational resolution are reported. Using resonant two-photon ionization and optical-optical double resonance spectroscopy, two vibronic bands were assigned and rotationally analyzed. In the B state, the three sodium nuclei perform a nearly free pseudorotational motion in the moat of a pseudo-Jahn–Teller potential that is characterized by a vibronic angular momentum quantum number j. In states with J > 0, each rotational level is split by Coriolis interaction. Rotational and Coriolis coupling parameters were determined and are discussed in terms of the dynamics of the vibronic coupling in this floppy molecule.

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Sun, Jin, Rui Hang Lin, Xiao Bo Wang, Xiao Feng Zhu, and Zhen Zhong Gao. "Sodium Silicate as Catalyst and Modifier for Phenol-Formaldehyde Resin." Applied Mechanics and Materials 184-185 (June 2012): 1198–206. http://dx.doi.org/10.4028/www.scientific.net/amm.184-185.1198.

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The novel adhesives were prepared using PF resin as matrix and sodium silicate as modification additive. It was proved by Fourier transform infrared spectrometer (FTIR) that silicon-oxygen bonds had been successfully introduced to the structure of PF resin. Boiling water extraction (BWE)，scanning electron microscopy (SEM)，thermogravimetric analyzer (TGA) and differential scanning calorimetry (DSC) were used to characterize the structure of PF resin modified with sodium silicate (Na2SiO3-PF). The test results show that sodium silicate is an effective modifier to PF resin which lessen the brittleness, accelerate the cure rate and enhance the boiling water resistance of PF resin as well. The FTIR，TGA and DSC test results also show that the structure of PF resin has been changed by sodium silicate.

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50

Hill, Geoffrey S., David G. Holah, Stephen D. Kinrade, Todd A. Sloan, Vincent R. Magnuson, and Valery Polyakov. "The X-ray structure of a sodium peroxide hydrate, Na2O2•8H2O, and its reactions with carbon dioxide: relevance to the brightening of mechanical pulps." Canadian Journal of Chemistry 75, no. 1 (January 1, 1997): 46–51. http://dx.doi.org/10.1139/v97-006.

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The main component of the solid originally believed to be a peroxosilicate with pulp-brightening properties has been shown to be Na2O2•8H2O. The solid crystallizes in the monoclinic space group C2/c, with an empirical formula H8O5Na, and with a = 14.335(3), b = 6.461(1), c = 11.432(2) Å, β = 118.28(3)°, and Z = 8. The centrosymmetric structure consists of a peroxide anion with an O—O distance of 1.499(2) Å. Each of these oxygen atoms is at the apex of an approximate square-based pyramid, the base of which consists of four oxygen atoms of water molecules. The bases of the two pyramids are staggered when viewed down the peroxide bond. Each sodium is at the centre of an approximate octahedron of water molecules, four of which bridge other sodium atoms and two bridge to the peroxide anions. One hydrogen atom of each of these two water molecules is terminal and the other two are hydrogen bonded to peroxide oxygen atoms. The compound reacts very rapidly with CO2 in moist air to form Na2CO3, but in drier conditions, formation of the carbonate can take many days and proceeds via a percarbonate, believed to be Na2CO4. This has been identified by infrared spectroscopy and X-ray powder diffraction and can persist for long periods in dry air. Key words: sodium peroxide hydrate, sodium percarbonate, pulp brightening, X-ray diffraction, infrared.

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Journal articles on the topic 'Oxygen and sodium nuclei structure'

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