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Trisodium scandium bis(orthoborate)  [cached]
Jinzhi Fang,Xinyuan Zhang,Jiyong Yao,Guochun Zhang
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812015061
Abstract: Single crystals of trisodium scandium bis(orthoborate), Na3Sc(BO3)2, have been obtained by spontaneous crystallization from an Na2O–Sc2O3–B2O3 melt. The crystal structure features a three-dimensional framework composed of planar [BO3]3 groups and distorted ScO6 octahedra with Na atoms in the cavities. The Sc atom occupies a special position (Wyckoff position 2b, site symmetry -1) and of the two Na atoms, one occupies a special position (Wyckoff position 2c, site symmetry -1).
Bis(acetylacetonato)oxido(triphenylphosphine oxide)vanadium(IV)
Hui Chen,Youtao Si,Changneng Chen,Qiutian Liu
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536807065439
Abstract: In the structure of the title compound, [V(C5H7O2)2O(C18H15OP)], the V atom adopts a slightly distorted octahedral geometry with its coordination completed by four O atoms of two acetylacetonate (acac) ligands, one oxo group and one O atom of the triphenylphosphine oxide (OPPh3) ligand.
Tris{N-[bis(dimethylamino)phosphinoyl]-2,2,2-trichloroacetamido}(triphenylphosphine oxide)holmium(III)
Oleksiy V. Amirkhanov,Ivan O. Marchenko,Olesia V. Moroz,Tetyana Yu. Sliva
Acta Crystallographica Section E , 2010, DOI: 10.1107/s160053681001665x
Abstract: In the title compound, [Ho(C6H12Cl3N3O2P)3(C18H15OP)], the HoIII ion is surrounded by six O atoms from the three bidentate N-[bis(dimethylamino)phosphinoyl]-2,2,2-trichloroacetamido ligands (L ) and by one O atom from the triphenylphosphine oxide ligand, with the formation of a distorted monocapped octahedron. In one ligand L , the trichloromethyl group is rotationally disordered between two orientations in a 1:1 ratio, while two dimethylamino groups in another ligand L are disordered between two conformations, each with the same 1:1 ratio.
catena-Poly[[[aquacopper(II)]bis[μ-bis(3,5-dimethyl-1H-pyrazol-4-yl) selenide]] bis(tetrafluoridoborate) bis(triphenylphosphine oxide) monohydrate]
Maksym Seredyuk,Kateryna O. Znovjyak,Yurii S. Moroz,Vadim A. Pavlenko
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810012997
Abstract: The title compound, {[Cu(C10H14N4Se)2(H2O)](BF4)2·2C18H15PO·H2O}n, has a polymeric structure where each CuII ion adopts a square-pyramidal coordination constituted by four N atoms of pyrazole moieties in the equatorial plane and an axial O atom of a water molecule. A pair of bis(3,5-dimethyl-1H-pyrazol-4-yl) selenide ligands bridges the CuII centres into a chain extending along the c axis. The water molecules, anions and triphenylphosphine oxide molecules are involved in intermolecular hydrogen bonding, which links the chains into a three-dimensional network.
cis-Bis(nitrato-κ2O,O′)bis(triethylphosphine oxide-κO)nickel(II)  [cached]
Rüdiger W. Seidel
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809015724
Abstract: In the title compound, [Ni(NO3)2(C6H15OP)2], the NiII ion, lying on a crystallographic twofold axis, adopts a distorted octahedral coordination, consisting of O-donor atoms of two symmetry-related triethylphospine oxide and two bidentate nitrate ligands.
Lattice dynamics and a magnetic-structural phase transition in the nickel orthoborate $Ni_{3}(BO_{3})_{2}$  [PDF]
R. V. Pisarev,M. A. Prosnikov,V. Yu. Davydov,A. N. Smirnov,E. M. Roginskii,K. N. Boldyrev,A. D. Molchanova,M. N. Popova,M. B. Smirnov,V. Yu. Kazimirov
Physics , 2015,
Abstract: Nickel orthoborate $Ni_{3}(BO_{3})_{2}$ having a complex orthorhombic structure $P_{nnm}$ (#58, Z=2) of the kotoite type is known for quite a long time as an antiferromagnetic material below $T_{N}$ = 46 K, but up to now its physical properties including the lattice dynamics have not been explored. Six magnetic nickel $Ni^{2+}$ ions (S=1) in the unit cell are distributed over the 2a and 4f positions in the centers of distorted $[O_{6}]$ octahedra. The $[NiO_{6}]$ units are linked via rigid $[BO_{3}]$ groups and these structural particularities impose restrictions on the lattice dynamics and spin-phonon interactions. We performed the symmetry analysis of the phonon modes at the center of the Brillouin zone. The structural parameters and phonon modes were calculated using Dmol3 program. We report and analyze results of infrared and Raman studies of phonon spectra measured in all required polarizations. Most of the even and odd phonons predicted on the basis of the symmetry analysis and theoretical calculations were reliably identified in the measured spectra. Absorption measurements in the infrared region showed emergence of several very narrow and weak phonons at the magnetic ordering temperature $T_{N}$. This observation proves the existence of a structural phase transition not reported before which is evidently coupled intrinsically with the magnetic dynamics of $Ni_{3}(BO_{3})_{2}$. A clear evidence of spin-phonon interaction was observed for some particular phonons below $T_{N}$.
A 2:1 cocrystal of the cis and trans isomers of bis[1,1,1,5,5,5-hexafluoropentane-2,4-dionato(1−)-κ2O,O′]bis(4-phenylpyridine N-oxide-κO)copper(II)  [cached]
José A. Fernandes,Ana I. Ramos,Susana S. Braga,Filipe A. Almeida Paz
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810049196
Abstract: The title compound is a co-crystal of the cis and trans isomers, namely cis-bis[1,1,1,5,5,5-hexafluoropentane-2,4-dionato(1 )-κ2O,O′]bis(4-phenylpyridine N-oxide-κO)copper(II)–trans-bis[1,1,1,5,5,5-hexafluoropentane-2,4-dionato(1 )-κ2O,O′]bis(4-phenylpyridine N-oxide-κO)copper(II) (2/1), [Cu(C5HF6O2)2(C11H9NO)2]. In both isomers, the coordination geometry of the Cu2+ atom is octahedral, exhibiting typical Jahn–Teller distortion. The metal atom of the trans isomer is located on an inversion centre. In the cis isomer, the phenyl ring in one 4-phenylpyridine N-oxide ligand is disordered over two orientations in a 1:1 ratio. In the crystal, weak intermolecular C—H...F and C—H...O contacts establish connections between the cis and trans isomers.
Di(isothiocyanato)bis(4-methyl-4’-vinyl-2,2’-bipyridine) Ruthenium(II) Films Deposited on Titanium Oxide-Coated, Fluorine-Doped Tin Oxide for an Efficient Solar Cell  [PDF]
Yi Liu, Ryuichi Sugimoto, Katsuhiro Sumi
Green and Sustainable Chemistry (GSC) , 2013, DOI: 10.4236/gsc.2013.32011
Abstract: Dye-sensitized titanium oxide electrodes were prepared by immobilizing a novel ruthenium complex, di(isothiocy- anato)bis(4-methyl-4-vinyl-2,2-bipyridine)ruthenium(II) [(NCS)2(mvbpy)2Ru(II)] or the ruthenium complex/sodium 4-vinylbenzenesulfonate onto the surface of a titanium oxide-coated, fluorine-doped tin oxide (TiO2/FTO) electrode through a new electrochemically initiated film formation method, in which the electrolysis step and the film deposition step were individually performed. The incident photon-to-current conversion efficiency (IPCE) of the Ru complex film on a TiO2/FTO electrode was disappointedly insufficient (1.2% at 440 nm). In sharp contrast, the Ru(II) complex/so- dium 4-vinylbenzenesulfonate composite film deposited on the surface of a TiO2/FTO electrode showed maximum IPCE of 31.7% at 438 nm.
Tetra-μ-acetato-bis[(pyridine N-oxide)copper(II)](Cu—Cu)
Yue Cui,Qian Gao,Chao-Yan Zhang,Ya-Bo Xie
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809024222
Abstract: The molecule of the title binuclear copper(II) complex, [Cu2(CH3COO)4(C5H5NO)2], occupies a special position on a crystallographic inversion centre; the coordination environment of the CuII atom is slightly distorted square-pyramidal and is made up of four O atoms belonging to four acetate groups in the basal plane with the O atom of pyridine N-oxide ligand in the apical position. The Cu—Cu distance is 2.6376 (6) .
Synthesis of bis(3-{[2-(allyloxy)ethoxy]methyl}-2,4,6-trimethylbenzoyl)(phenyl)phosphine oxide – a tailor-made photoinitiator for dental adhesives  [cached]
Norbert Moszner,Iris Lamparth,J?rg Angermann,Urs Karl Fischer
Beilstein Journal of Organic Chemistry , 2010, DOI: 10.3762/bjoc.6.26
Abstract: Because of the poor solubility of the commercially available bisacylphosphine oxides in dental acidic aqueous primer formulations, bis(3-{[2-(allyloxy)ethoxy]methyl}-2,4,6-trimethylbenzoyl)(phenyl)phosphine oxide (WBAPO) was synthesized starting from 3-(chloromethyl)-2,4,6-trimethylbenzoic acid by the dichlorophosphine route. The substituent was introduced by etherification with 2-(allyloxy)ethanol. In the second step, 3-{[2-(allyloxy)ethoxy]methyl}-2,4,6-trimethylbenzoic acid was chlorinated. The formed acid chloride showed an unexpected low thermal stability. Its thermal rearrangement at 180 °C resulted in a fast formation of 3-(chloromethyl)-2,4,6-trimethylbenzoic acid 2-(allyloxy)ethyl ester. In the third step, the acid chloride was reacted with phenylphosphine dilithium with the formation of bis(3-{[2-(allyloxy)ethoxy]methyl}-2,4,6-trimethylbenzoyl)(phenyl)phosphine, which was oxidized to WBAPO. The structure of WBAPO was confirmed by 1H NMR, 13C NMR, 31P NMR, and IR spectroscopy, as well as elemental analysis. WBAPO, a yellow liquid, possesses improved solubility in polar solvents and shows UV–vis absorption, and a high photoreactivity comparable with the commercially available bisacylphosphine oxides. A sufficient storage stability was found in dental acidic aqueous primer formulations.
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