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Ben Fraj N.,Institute Superieur des science Appliquees et Technology | Omri S.,Faculte des science de Gafsa
Theoretical and Mathematical Physics | Year: 2010

We classify deformations of the standard embedding of the Lie superalgebra K(2) of contact vector fields on the (1, 2)-dimensional supercircle into the Lie superalgebra SΨD(S1{pipe}2) of pseudodifferential operators on the supercircle S1{pipe}2. The proposed approach leads to the deformations of the central charge induced on K(2) by the canonical central extension of SΨD(S1{pipe}2). © 2010 MAIK/Nauka. Source


Nagazi I.,CNRS Institute of Chemistry | Haddad A.,Institute Superieur des science Appliquees et Technology
Journal of Cluster Science | Year: 2013

A new organic-inorganic hybrid compound (2-AMP)4[Se2Mo5O21]·2H2O (1) [2-AMP = 2-aminopyridinium] has been synthesized and characterized by IR spectrum, UV-Vis spectra, 1H NMR spectroscopy, thermogravimetric analyses, cyclic voltammetry measurements and single crystal X-ray diffraction. Compound 1 crystallizes in the triclinic system with space group P-1 and a = 11. 451(6) Å, b = 13. 478(3) Å, c = 14. 037(2) Å, α = 108. 956(2)°, β = 96. 260(2)°, γ = 97. 174(3)°, Z = 2. The title compound contains four protonized 2-AMP cations, five distorted MoO6 octahedra and two SeO3 pyramids by sharing vertices and edges. These five Mo atoms are nearly coplanar, and two SeO3 pyramids lie on both sides of this plane. The interactions between [Se2Mo5O21]4- clusters are established through hydrogen contacts which involve selenium, water molecules and 2-aminopyridine cations to form a three-dimensional structure. © 2012 Springer Science+Business Media New York. Source


Chaalia S.,Institute Superieur des science Appliquees et Technology | Daran J.-C.,CNRS Coordination Chemistry | Haddad A.,Institute Superieur des science Appliquees et Technology
Structural Chemistry | Year: 2012

An organic-inorganic hybrid material based on paradodecatungstate anions and imidazolium cations, Na 2(HI m) 8(H 2W 12O 42)·10H 2O (HIm: imidazolium), has been synthesized under mildly acidic conditions. This compound was characterized by single-crystal X-ray diffraction, IR and UV-visible spectroscopies, and thermogravimetric and differential thermal analyses. The compound crystallizes in the triclinic P-1 space group with a = 11.6945(8) Å, b = 12.4782(6) Å, c = 14.0952(9) Å, a = 106.041(3)°, b = 109.338(2)°, c = 100.249(3)°, V = 1781.0(3) Å 3, and Z = 2. The crystal structure exhibits an infinite 1D inorganic structure built from [H 2W 12O 42]10 - clusters and sodium cations; adjacent chains are further joined up by hydrogenbonding interactions between protonated imidazole cations, water molecules, and polyoxoanions, to form a 3D supramolecular architecture.© Springer Science+Business Media, LLC 2011. Source


Nagazi I.,CNRS Institute of Chemistry | Haddad A.,Institute Superieur des science Appliquees et Technology
Materials Research Bulletin | Year: 2012

An inorganic compound formulated as Rb 4[Se 2Mo 5O 21]·2H 2O (1) has been isolated by conventional solution method and structurally characterized by single-crystal X-ray diffraction methods, scanning electron microscopy (SEM), powder XRD, IR, UV-vis spectra, and cyclic voltammetry measurements. This compound crystallizes in the monoclinic system, space group C2 with unit a = 19.701 (3) , b = 10.296 (2) , c = 12.134 (4) , β = 106.96 (2)° and Z = 4. The crystal structure of (1) is built up from a Strandberg clusters connected through hydrogen-bonding interactions into a three-dimensional supramolecular network. © 2011 Elsevier Ltd. All rights reserved. Source


Chaalia S.,Institute Superieur des science Appliquees et Technology | Ayed B.,Institute Superieur des science Appliquees et Technology | Haddad A.,Institute Superieur des science Appliquees et Technology
Journal of Chemical Crystallography | Year: 2012

Brown single crystals of the potassium-manganese arsenate K 2Mn 3(AsO 4) 3 were prepared by solid-state reaction and characterized by X-ray diffraction, infrared spectroscopy and complex impedance measurements. The compound crystallizes in the monoclinic space group C2/c with a = 12.490(1) Å, b = 13.013(1) Å, c = 6.888(1) Å, β = 114.46(2)°and Z = 4. The crystals belong an alluaudite-like structure characterized by the X(2)X(1)M(1)M(2) 2(AsO 4) 3 formula, in which the X sites are occupied by potassium cations and the M sites contain the manganese atoms. The manganese-arsenate framework is formed by chains of edge-sharing MnO 6 octahedra linked together via the AsO 4 tetrahedra, yielding two distinct tunnels of potassium cations occupation. Pure solid K 2Mn 3(AsO 4) 3 shows modest ionic conductivity with an activation energy of 0.83 eV in the temperature range from 500 to 700 K. © 2012 Springer Science+Business Media, LLC. Source

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