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Li Wen - - 2012
Li-Na ternary amidoborane, Na[Li(NH(2)BH(3))(2)], was recently synthesized by reacting LiH and NaH with NH(3)BH(3). This mixed-cation amidoborane shows improved dehydrogenation performance compared to that of single-cation amidoboranes, i.e., LiNH(2)BH(3) and NaNH(2)BH(3). In this paper, we synthesized the Li-Na ternary amidoborane by blending and re-crystallizing equivalent LiNH(2)BH(3) and NaNH(2)BH(3) in tetrahydrofuran ...
Pérez-Flores J C - - 2012
A detailed structural and electrochemical study of the ion exchanged Li(2)Ti(6)O(13) titanate as a new anode for Li-ion batteries is presented. Subtle structural differences between the parent Na(2)Ti(6)O(13), where Na is in an eightfold coordinated site, and the Li-derivative, where Li is fourfold coordinated, determine important differences in the electrochemical ...
Sun Jiaying - - 2012
Docking studies of pyrrolidine derivatives indicated that Trp178, Arg371 and Tyr406 were the key residues in the active pocket of influenza neuraminidase (NA). Hydrogen bond and electrostatic factors mainly influenced interactions between pyrrolidine derivatives and NA. Moreover, there was a significant correlation between binding affinity (total scores) and the experimental ...
Braunschweig Holger - - 2012
The synthesis and structural characterization of the first tin-bridged ansa half-sandwich complexes via a two-step protocol from Na[η(5)-C(5)H(5)Ru(CO)(2)] and in situ generated Na[η(5)-C(5)H(5)Ni(CO)] are presented. Both compounds are characterized by multinuclear NMR spectroscopy and single-crystal diffraction.
Liu Wei - - 2012
DNA sequences with guanine repeats can form G-quartets that adopt G-quadruplex structures in the presence of specific metal ions. Using circular dichroism (CD) and ultraviolet-visible (UV-Vis) spectroscopy, we determined the spectral characteristics and the overall conformation of a G-quadruplex of PS2.M with an oligonucleotide sequence, d(GTG(3)TAG(3)CG(3)TTG(2)). UV-melting curves demonstrate that ...
Qin Chao - - 2012
A family of polyoxometalate compounds based on Preyssler anions and lanthanide cations, K(5)Na(5)[{Pr(4)(H(2)O)(12)(pydc)(4)}{Na(H(2)O)P(5)W(30)O(110)}]·46H(2)O (1, H(2)pydc = pyridine-2,6-dicarboxylic acid), Na(7)[{Pr(4)(H(2)O)(20)(pydc)(2)(Ac)}{Na(H(2)O)P(5)W(30)O(110)}]·23H(2)O (2), and Na(10)H(2) [{Ln(2)(H(2)O)(10)(pydc)(2)}{Na(H(2)O)P(5)W(30)O(110)}]·XH(2)O (Ln = Sm 3, Eu 4, Gd 5; X = 11 for 3 and 5, 13 for 4), have been synthesized and characterized by elemental analysis and ...
Fry Allyson M - - 2011
Na1.5Ag1.5MoO3F3 and Na1.5Ag1.5WO3F3 have been synthesized by solid state reactions and structurally cha-racterized using synchrotron X-ray and neutron powder diffraction. Unlike the vast majority of salts containing [MO3F3]3- anions (M = Mo, W) the oxyfluoride groups in Na1.5Ag1.5MoO3F3 and Na1.5Ag1.5WO3F3 are orientationally ordered, so that the Na+ ions are coordinated ...
Yang Yu - - 2012
In the title heterodinuclear complex, [CuNa(BF(4))(C(8)H(7)O(3))(2)](n), the Cu(II) ion is four-coordinated by four O atoms of two 2-formyl-6-meth-oxy-phenolate ligands, giving rise to a square-planar geometry. The Na(+) ion is six-coordinated by four O atoms from the two ligands and two F atoms of two tetra-fluoridoborate anions. The tetra-fluoridoborate anion links ...
Lü Jian - - 2011
Two isostructural organic-inorganic hybrid solid materials based on cucurbituril derivatives and polyoxometalates, {[K(2)(H(2)O)(2)Na(2)(H(2)O)(2)Na(2)(H(2)O)(6)](P(2)W(18)O(62))(Me(10)Q(5))(2)}·∼7H(2)O (1) and {[Rb(2)(H(2)O)(2)Na(2)(H(2)O)Na(2)(H(2)O)(4)](P(2)W(18)O(62))(Me(10)Q(5))(2)}·∼8H(2)O (2), which exhibit reversible photochromic properties as well as excellent photocatalytic activities toward the degradation of methyl orange (MO) and rhodamine-B (RB) under visible light irradiation, are reported.
Boyko Alexander N - - 2011
In the title compound, [CoNa(2)(C(7)H(3)NO(4))(2)(H(2)O)(2)](n), the Co(II) atom is coordinated by two pyridine N atoms and four carboxyl-ate O atoms from two doubly deprotonated pyridine-2,6-dicarboxyl-ate ligands in a distorted octa-hedral geometry. One Na(+) cation is coordinated by three carboxyl-ate O atoms and two water mol-ecules and the other is coordinated ...
Frazier Brenda A - - 2011
A series of Werner complexes featuring the tridentate ligand smif, that is, 1,3-di-(2-pyridyl)-2-azaallyl, have been prepared. Syntheses of (smif)(2)M (1-M; M = Cr, Fe) were accomplished via treatment of M(NSiMe(3))(2)(THF)(n) (M = Cr, n = 2; Fe, n = 1) with 2 equiv of (smif)H (1,3-di-(2-pyridyl)-2-azapropene); ortho-methylated ((o)Mesmif)(2)Fe (2-Fe) and ...
Schleid Thomas - - 2011
Scheelite-type NaNd[MoO(4)](2) contains one crystallographic position (site symmetry [Formula: see text]) for the large cations, which is mixed-occupied by Na(+) and Nd(3+) cations in a 1:1 molar ratio. Thus, both are surrounded by eight O atoms in the shape of a trigonal dodeca-hedron. Furthermore, the structure consists of crystallographically unique ...
Bénaud Olivier - - 2011
In contrast to the neutral macrocycle [UN*(2)(N,C)] (1) [N* = N(SiMe(3))(3); N,C = CH(2)SiMe(2)N(SiMe(3))] which was quite inert toward I(2), the anionic bismetallacycle [NaUN*(N,C)(2)] (2) was readily transformed into the enlarged monometallacycle [UN*(N,N)I] (4) [N,N = (Me(3)Si)NSiMe(2)CH(2)CH(2)SiMe(2)N(SiMe(3))] resulting from C-C coupling of the two CH(2) groups, and [NaUN*(N,O)(2)] (3) [N,O ...
Veliath Elizabeth - - 2011
We have synthesized five analogs of c-di-GMP with different substituents at the guanine C8 position, to study their effects on the metal-dependent polymorphism we had previously demonstrated for the parent compound. Of these, only the K(+) salt of c-di-Br-GMP, 2, forms higher order complexes, predominantly two different syn octamolecular ones. ...
Hamza Hamadi - - 2011
The title compound, silver disodium trimolybdenum(VI) nonaoxide arsenate, AgNa(2)Mo(3)O(9)AsO(4), was prepared by a solid-state reaction at 808 K. The structure consists of an infinite (Mo(3)AsO(13))(n) ribbon, parallel to the c axis, composed of AsO(4) tetra-hedra and MoO(6) octa-hedra sharing edges and corners. The Na and Ag ions partially occupy several independent ...
Zhao Dan - - 2011
The asymmetric unit of title compound contains three Na(+), one Al(3+), three P(5+) and eight O(2-) atoms, with one Na(+) atom lying on a twofold rotation axis and one Na(+) and one P(5+) atom on fourfold rotoinversion axes. The fundamental building units of the title structure are isolated PO(4) tetra-hedra, ...
Ahmad Iqbal - - 2011
The present work is based on a study of the effect of some vitamins such as riboflavin (RF), nicotinamide (NA) and alpha-tocopherol (TP) on the photodegradation of ascorbic acid (vitamin C) (AH(2) ) in oil-in-water cream formulations using a UV irradiation source. A UV spectrophotometric and the official iodimetric methods ...
Gundogdu Evren - - 2011
This study aims to prove the complexation of cefpodoxime proxetil (CP) by hydroxypropyl-β-cyclodextrin (HP-β-CD) in the presence of sodium carboxymethyl cellulose (Na CMC), and makes a comparison of commercial tablets by dissolution and antimicrobial activity studies. The CP-HP-β-CD complex was prepared by kneading method and characterized by SEM, FTIR and ...
Maluangnont Tosapol - - 2011
A series of ternary graphite intercalation compounds (GICs) of alkali metal cations (M = Li, Na, K) and diamines [EN (ethylenediamine), 12DAP (1,2-diaminopropane), and DMEDA (N,N-dimethylethylenediamine)] are reported. These include stage 1 and 2 M-EN-GIC (M = Li, d(i) = 0.68-0.84 nm; M = Na, d(i) = 0.68 nm), stage ...
Pradhan Kalpataru - - 2011
Recent work has shown that BO(2) which is a superhalogen with an electron affinity of 4.46 eV, can be used as building block of a new class of molecules∕clusters whose electron affinities can exceed that of BO(2). This class of molecules was named hyperhalogens and the concept was illustrated by ...
Jones B E H - - 2011
PURPOSE: To examine (1) the effect of organic (poultry manure) and inorganic (residue mud and phosphogypsum) amendments on nutrient leaching losses from residue sand and (2) whether amendments improve the growth of plants in residue sand. METHODS: Leaching columns were established using residue sand. The phosphogypsum-treated surface layer (0-15 cm) was ...
Cheng Xian - - 2011
A unique tubular molecular-assembly, constructed by β-cyclodextrin and Na[Ni(mnt)(2)], was identified by X-ray crystallography. Inclusion complex Na[Ni(mnt)(2)]@β-cyclodextrin (1) crystallized in space group P2(1)2(1)2 as hydrated head-to-head, tail-to-tail, and head-to-tail host pipelines with negatively charged [Ni(mnt)(2)](-) guests included, exhibiting a 3 : 1 (host : guest) stoichiometry. The hydrophilic transition-metal coordination compound (Na[Ni(mnt)(2)]) was embedded ...
van Merwe Kina - - 2011
In the title compound, Na(2)[Co(CH(4)O(6)P(2))(2)(H(2)O)(2)]·2H(2)O, the asymmetric unit is composed of one methyl-enediphospho-nate ligand and one water mol-ecule, which both are coordinated to a Co(II) atom, as well as a non-coordinated water mol-ecule and a sodium cation. The Co(II) atom occupies a special position on a crystallographic inversion centre. The ...
Logemann Christian - - 2011
The reaction of Au(OH)(3) and oleum (65% SO(3)) in the presence of M(2)SO(4) (M = Li, Na) afforded yellow single crystals of Li[Au(S(2)O(7))(2)] (triclinic, P1̅, Z = 1, a = 532.20(3), b = 649.69(4), c = 836.72(5) pm, α = 107.982(2)°, β = 90.171(2)°, γ = 102.583(2)°, V = 267.80(3) ...
Solis-Ibarra Diego - - 2011
Crystallization of Na(2)VOP(2)O(7) from its aqueous solution results in formation of a one-dimensional inorganic polymer {Na(2)VO(H(2)O)P(2)O(7)·7H(2)O}(n) (1). When this polymer is dehydrated at elevated temperatures this polymer undergoes a phase transition to form the two-dimensional framework β-Na(2)VOP(2)O(7), which although previously reported had been difficult to access. Exchanging lithium for sodium ...
Liu Fu-Hong - - 2011
The title compound {systematic name: poly[[μ(7)-(2R)-2-amino-3-sulfonato-propano-ato]disodium]}, [Na(2)(C(3)H(5)NO(5)S)](n), was obtained through solvent-thermal reaction of l-cysteic acid and aqueous sodium hydroxide. The monomer consists of two Na(+) cations that are coordinated to the deprotonated amino acid. The latter acts as donor utilizing all available coordination sites, viz. the amino, the carboxyl-ate and ...
Dhananjaya N - - 2011
Gd(1.95)Eu(0.04)M(0.01)O(3) (M=Li(+), Na(+), K(+)) nanophosphors have been synthesized by a low temperature solution combustion (LSC) method. Powder X-ray diffraction pattern (PXRD), scanning electron microscopy (SEM), UV-vis and photoluminescence (PL) measurements were carried out to characterize their structural and luminescent properties. The excitation and emission spectra indicated that the phosphor could ...
Van Ausdall Bret R - - 2011
Combination of 1,3-bis(2,6-diisopropylphenyl)imidazolum-2-carboxylate (IPrCO2) with the Lewis acids MBPh4, where M=Li or Na, provided two separate complexes. The crystal structures of these complexes revealed that coordination to NaBPh4 yielded a dimeric species yet coordination of IPrCO2 with LiBPh4 yielded a monomeric species. Combination of 1,3-bis(2,4,6-trimethylphenyl)imidazolum-2-carboxylate (IMesCO2) with LiBPh4 also afforded ...
Tofan Daniel - - 2011
The Nb-P triple bond in [P≡Nb(N[Np]Ar)(3)](-) (Np = CH(2)(t)Bu; Ar = 3,5-Me(2)C(6)H(3)) has produced the first case of P(4) activation by a metal-ligand multiple bond. Treatment of P(4) with the sodium salt of the niobium phosphide complex in weakly coordinating solvents led to formation of the cyclo-P(3) anion [(P(3))Nb(N[Np]Ar)(3)](-). Treatment ...
Rubio-Marcos Fernando - - 2011
This article reviews on the use of Raman spectroscopy for the study of (K,Na,Li)(Nb,Ta,Sb)O(3) lead-free piezoceramics. Currently, this material appears to be one of the most interesting and promising alternatives to the well-known PZT piezoelectric materials. In this work, we prepare piezoceramics with different stoichiometries and study their structural, ferroelectric, ...
Krogman Jeremy P - - 2011
At room temperature, the early/late heterobimetallic complex Co((i)Pr(2)PNMes)(3)Zr(THF) has been shown to oxidatively add CO(2), generating (OC)Co((i)Pr(2)PNMes)(2)(μ-O)Zr((i)Pr(2)PNMes). This compound can be further reduced under varying conditions to generate either the Zr oxoanion (THF)(3)Na-O-Zr(MesNP(i)Pr(2))(3)Co(CO) or the Zr carbonate complex (THF)(4)Na(2)(CO(3))-Zr(MesNP(i)Pr(2))(3)Co(CO). Additionally, reactivity of the CO(2)-derived product has been observed with PhSiH(3) ...
Zhang Hao - - 2011
In the present paper, the possible ion associated species in pure Na(2)SO(4) and mixed Na(2)SO(4)∕MgSO(4) aqueous solutions are investigated via the ab initio method at the HF∕6-31+G∗ level. The vibrational v(1)-SO(4) (2-) band is analyzed. For the unhydrated species, when the number of metal ions around the SO(4) (2-) ion ...
Li Qingzhong - - 2011
Quantum chemical calculations have been performed to study the complex of MCN-LiCN-XCCH (M = H, Li, and Na; X = Cl, Br, and I). The aim is to study the cooperative effect between halogen bond and lithium bond. The alkali metal has an enhancing effect on the lithium bond, making ...
Negi Jagmohan Singh - - 2011
Important mineral elements (Fe, Zn, Mn, Cu, Co, Na, K, Ca and Li) were determined in the leaves and roots of Swertia paniculata collected from three different altitudes in three seasons using atomic absorption spectroscopy. The highest concentrations of Zn, Cu, Mn, Fe, Co, Na, K, Ca and Li were ...
Carlier D - - 2011
Manganese substituted sodium cobaltate, Na(2/3)Co(2/3)Mn(1/3)O(2), with a layered hexagonal structure (P2-type) was obtained by a co-precipitation method followed by a heat treatment at 950 °C. Powder X-ray diffraction analysis revealed that the phase is pure in the absence of long-range ordering of Co and Mn ions in the slab or ...
Ohta H - - 2011
We addressed the so-far unresolved issue concerning the Co valence in the superconducting bilayer hydrated Na_{x}CoO_{2}·yH_{2}O (x∼0.35, y∼1.3) using soft x-ray absorption spectroscopy at the Co-L_{2,3} and O-K edges. We find that the valence state of the Co lies in a narrow range from +3.3 to +3.4 for all studied ...
Ashley Andrew Edward - - 2011
A new family of electron-deficient tris(aryl)boranes, B(C6F5)3-n(C6Cl5)n (n = 1-3) has been synthesized, permitting an investigation into the steric and electronic effects resulting from the gradual replacement of C6F5 with C6Cl5 ligands. B(C6F5)2(C6Cl5) (3) is accessed via C6Cl5BBr2, itself prepared from donor-free Zn(C6Cl5)2 and BBr3. Reaction of C6Cl5Li with BCl3 ...
Campbell Ross - - 2011
The surprising transformation of the saturated diamine (iPr)NHCH2CH2NH(iPr) to the unsaturated diazaethene [(iPr)NCH=CHN(iPr)]2- via the synergic mixture nBuM, (tBu)2Zn and TMEDA (where M = Li, Na; TMEDA = N,N,N',N'-tetramethylethylenediamine) has been investigated by multinuclear NMR spectroscopic studies and DFT calculations. Several pertinent intermediary and related compounds (TMEDA)Li[(iPr)NCH2CH2NH(iPr)]Zn(tBu)2 (3), (TMEDA)Li[(iPr)NCH2CH2CH2N(iPr)]Zn(tBu) (5), ...
Myers Thomas W - - 2011
Hydrogen abstraction by aluminum(III)-oxo intermediates via reaction pathways reminiscent of late transition metal chemistry has been observed. Oxidation of M(+)[(IP(2-))(2)Al](-) (IP = iminopyridine, M = Na, Bu(4)N) yielded [Na(THF)(DME)][(IP(-))(IP(2-))Al(OH)] (3) or [(IP(-))(2)Al(OH)] (4), via O-atom transfer and subsequent C-H activation or proton abstraction, respectively.
Tan Huaqiao - - 2011
Two asymmetric polyoxomolybdates Na(6){Mo(2)O(5)[(Mo(2)O(6))NH(3)CH(2)CH(2)CH(2)C(O)(PO(3))(2)](2)}·16H(2)O (1) and (NH(4))(7)Na{MoO(2)[(Mo(2)O(6))NH(3)CH(2)CH(2)CH(2)C(O)(PO(3))(2)]}(4)·H(2)O (2) have been synthesized by the reactions of alendronic acid with molybdate. Structure analysis revealed that the polyoxoanions 1 and 2 can be described as dimeric and tetrameric aggregates of the {MoO(3)[(Mo(2)O(6))NH(3)CH(2)CH(2)CH(2)C(O)(PO(3))(2)]} units respectively. Their tetrabutylammonium salts show efficient selective oxidation of benzyl ...
Naruke Haruo - - 2011
Enantiopure crystals of K(1.3)Na(3.2)H(6.5)[l-Pr(PW(11)O(39))(2)]·8.3l-proline·21.5H(2)O (1), K(1.3)Na(3.2)H(6.5)[d-Pr(PW(11)O(39))(2)]·8.3d-proline·17H(2)O (2), and K(1.3)Na(3.2)H(6.5)[l-Er(PW(11)O(39))(2)]·8.3l-proline·22.5H(2)O (3) were successfully obtained by using l- and d-proline (pro) as chiral auxiliary agents. In these crystals, l- and d-[Ln(PW(11)O(39))(2)](11-) anions are attached by two l- and d-pro molecules, respectively, through a O···N hydrogen-bonding interaction between the square-antiprismatic LnO(8) center and ...
Samal Saroj L - - 2011
Na(6)Cd(16)Au(7) has been synthesized via typical high-temperature reactions, and its structure refined by single crystal X-ray diffraction as cubic, Fm3̅m, a = 13.589(1) Å, Z = 4. The structure consists of Cd(8) tetrahedral star (TS) building blocks that are face capped by six shared gold (Au2) vertexes and further diagonally ...
Baillie Sharon E - - 2011
Poly[bis(μ(3)-trimethylsilylmethanolato)tetrakis(μ(2)-trimethylsilylmethyl)dimagnesiumdisodium], [Na(2)Mg(2)(C(4)H(11)OSi)(2)(C(4)H(11)Si)(4)](n), was obtained from the controlled exposure to oxygen of the unsolvated sodium magnesate [NaMg(CH(2)SiMe)(3)](n). Exhibiting a centrosymmetric (Z' = 1/2) dimeric core of a heterobimetallic eight-membered cationic ring, hosting two alkoxide ligands at its core, the title compound forms a two-dimensional coordination polymer in the crystallographic bc plane ...
Sun Dong-Qing - - 2011
In the title complex, [Na(C(2)HCl(2)O(3)S(2))(C(10)H(20)O(5))], there are two independent complex units in the asymmetric unit, one of which has a 55:45% disorder in the 15-crown-5 component. The coordination sphere about the Na atom in each complex unit comprises five bonds to O atoms of the crown ether [Na-O = 2.390 (7)-2.466 (6) Å] ...
Armstrong D R - - 2011
More usually thought of as a base, the sodium zincate [(TMEDA)·Na(μ-TMP)(μ-(t)Bu)Zn((t)Bu)] 1 can undergo single electron transfer with TEMPO to give [(TMEDA)·Na(μ-TMP)(μ-TEMPO(-))Zn((t)Bu)] 2 and [(TMEDA)·Na(μ-TEMPO(-))(2)Zn((t)Bu)] 3; and with chalcone [PhCOCH[double bond, length as m-dash]CHPh] gives [{(TMEDA)·Na(μ-TMP)Zn((t)Bu)}(2)(μ-OCPhCH[double bond, length as m-dash]CHPhCHPhCH[double bond, length as m-dash]CPh-μ-O)] which contains two chalcone units C-C ...
Pauvert Olivier - - 2011
The structure of <i>A</i>F-ZrF<sub>4</sub> systems (<i>A</i><sup>+</sup>=Li<sup>+</sup>, Na<sup>+</sup>, K<sup>+</sup>) compounds in the liquid state is studied using an approach combining EXAFS spectroscopy with molecular dynamics simulations. A very good agreement is observed between the two techniques, which allows us to propose a quantitative description of the liquids. From the Zr<sup>4+</sup> solvation ...
Zheng W-J - - 2011
Mass spectrometry and photoelectron spectroscopy together with first principles theoretical calculations have been used to study the electronic and geometric properties of the following sodium-tin, cluster anion∕neutral cluster combinations, (Na(n)Sn(4))(-)∕(Na(n)Sn(4)), n = 0-4 and (NaSn(m))(-)∕(NaSn(m)), m = 4-7. These synergistic studies found that specific Zintl anions, which are known to ...
Gowda B Thimme - - 2011
In the title compound, Na(+)·C(6)H(4)BrClNO(2)S(-)·1.5H(2)O, one water mol-ecule has crystallographically imposed twofold symmetry. The Na(+) cation shows a pseudo-octa-hedral coordination provided by three O atoms of water mol-ecules and three sulfonyl O atoms of different N-bromo-2-chloro-benzene-sulfonamidate anions. The S-N distance of 1.579 (6) Å is consistent with an S=N double-bond character. The ...
Léon Aline - - 2011
Innermolecular motion in Na(3)AlH(6) gives rise to a Lorentzian spectrum with a wavenumber-independent width of about 1  µeV at 180 °C, which is probably due to the rotation of AlH(6) tetrahedra. There is no such quasielastic line in NaAlH(4) or NaH. Based on this finding, time-resolved measurements on the neutron backscattering ...
Jin Geng Bang - - 2011
Dark green crystals of (NpO(2))(3)(OH)(SeO(3))(H(2)O)(2)·H(2)O (1) have been prepared by a hydrothermal reaction of neptunyl(V) and Na(2)SeO(4) in an aqueous solution at 150 °C, while green plates of Na(NpO(2))(SeO(3))(H(2)O) (2) have been synthesized by evaporation of a solution of neptunyl(V), H(2)SeO(4), and NaOH at room temperature. Both compounds have been ...
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