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Moutataouia M.,Laboratoire Of Physico Chimie Des Materiaux Inorganiques | Lamire M.,Laboratoire Of Physico Chimie Des Materiaux Inorganiques | Taibi M.,Mohammed V University
MATEC Web of Conferences | Year: 2013

New materials based glassy phosphates and transition elements A 2MnMP2O10 (A = Li, Na, K) and (M = Mo, W) were prepared by direct fusion of the mixture of the reactants followed by quenching in the air. Analysis by X-ray diffraction showed that the obtained materials are amorphous. Differential scanning calorimetry DSC was used to determine the glass transition (Tg) and crystallization (Tc) temperatures. The thermal stability of tungsten glasses is higher than that of molybdenum ones. Tungsten plays, certainly, a role of cross-linking polyphosphate groups by creating more covalent new bonds P-O-W and W-O-W. Moreover, it has been shown that lithium glasses are more stable than sodium and potassium, probably due to the potassium hygroscopy. Raman analysis confirms that the studied glasses have similar structures and the predominant structural units are PO4, P 2O7 and MO6 polyhedra (M = W, Mo, Mn). © Owned by the authors, published by EDP Sciences, 2013. Source


Moutataouia M.,Laboratoire Of Physico Chimie Des Materiaux Inorganiques | Lamire M.,Laboratoire Of Physico Chimie Des Materiaux Inorganiques | Saadi M.,Mohammed V University | El Ammari L.,Mohammed V University
Acta Crystallographica Section E: Structure Reports Online | Year: 2012

The structure of the title compound, K2Na3P 3O10, is characterized by open chains of three PO 4 tetra-hedra linked by single oxygen bridges. The P 3O10 groups have crystallographic twofold symmetry, with the central P atom being located on the twofold rotation axis. One of the sodium ions lies on a centre of inversion, whereas all the remaining atoms are in general positions. The structure is isotypic with that of the high-temperature form of Na5P3O10 phase I. © Moutataouia et al. 2012. Source


Moutataouia M.,Laboratoire Of Physico Chimie Des Materiaux Inorganiques | Lamire M.,Laboratoire Of Physico Chimie Des Materiaux Inorganiques | Saadi M.,Mohammed V University | El Ammari L.,Mohammed V University
Acta Crystallographica Section E: Structure Reports Online | Year: 2012

The structure of the title compound, NaK5Ni5(P 2O7)4, is characterized by the presence of two crystallographically independent P2O7 groups with different conformations. The conformation of the first P2O 7 group is eclipsed, whereas that of the second is staggered. All atoms are in general positions except for two nickel and one potassium ions which lie on symmetry centers. Moreover, the structure exhibits disorder of the cationic sites with one general position fully occupied equally by Na + and Ni2+ cations. This mixed site is surrounded by five O atoms forming a square-based pyramid. The crystal structure consists of edge-sharing [NiO6] octahedra forming infinite zigzag chains [Ni 3O14] running parallel to [100]. Adjacent chains are connected through apices to P2O7 groups and to another [NiO6] or to a [KO6] octahedron. The resulting three-dimensional framework presents intersecting tunnels running along the [010] and [001] directions in which the seven- and nine-coordinated potassium cations are located. The crystal structure of this new phosphate represents a new structural type. Source


Moutataouia M.,Laboratoire Of Physico Chimie Des Materiaux Inorganiques | Lamire M.,Laboratoire Of Physico Chimie Des Materiaux Inorganiques | Saadi M.,Mohammed V University | El Ammari L.,Mohammed V University
Acta Crystallographica Section E: Structure Reports Online | Year: 2014

The structure of the title compound is characterized by the presence of two different anions, (PO4)3- and (P2O 7)4- with an eclipsed conformation. The crystal structure consists of edge-sharing [NiO6] octahedra forming an [Ni 3O14] chain running parallel to [001]. Adjacent chains are connected through edges and apices to PO4and P2O 7 groups in such a way as to build a three-dimensional host lattice. The resulting framework presents intersecting tunnels running along [010] and [101] in which the 11-coordinated potassium cation is located. The crystal structure of this new phosphate probably represents a new structural type. Source


Moutataouia M.,Laboratoire Of Physico Chimie Des Materiaux Inorganiques | Lamire M.,Laboratoire Of Physico Chimie Des Materiaux Inorganiques | Saadi M.,Mohammed V University | El Ammari L.,Mohammed V University
Acta Crystallographica Section E: Structure Reports Online | Year: 2014

The poly-phosphate Li2Mn(PO3)4 was synthesized and its structure characterized from powder diffraction data by Averbuch-Pouchot and Durif [J. Appl. Cryst. (1972), 5, 307-308]. These authors showed that the structure of this phosphate is isotypic to that of Li 2Cd(PO3)4, as confirmed by the present work. The structure is built from infinite zigzag polyphosphate chains, [(PO 3)-] n , extending along [010]. These polyphosphate chains are connected by sharing vertices with MnO6 octahedra (site symmetry.m.) and Li2O7 polyhedra, which form also chains parallel to [010]. Adjacent chains are linked by common vertices of polyhedra in such a way as to form porous layers parallel to (100). The three-dimensional framework delimits empty channels extending along [010]. Source

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