Ahmed Driss

Tetrakis(1,4-anisidinium) cyclotétraphosphate hexahydrate

The asymmetric unit of the title compound, 4C7H10NO+·P4O124−·6H2O, consists of two 1,4-anisidinium cations, two PO4 tetrahedra, which form one half of a cyclic P4O124− anion, and three water molecules. The P4O124− anion is disordered around an inversion centre and exhibits two forms, with occupancies of 0.55 and 0.45. Two-dimensional layers of P4O12 rings connected to water molecules via weak hydrogen bonds run parallel to the bc plane. The organic cations are linked to these inorganic layers only by N—H⋯O hydrogen bonds. The methoxy groups of the organic cations are not involved in significant intermolecular interactions, leading to a two-dimensional structure.

Structure de RbAlAs2O7

Rubidium aluminium pyroarsenate, M r =374.29, triclinic, PI, a=8.233 (5), b=6.34 (2), c=6.241 (5) A, α=102.6 (1), β=103.89 (7), γ=96.7 (1) o , V=303.9 A 3 , Z=2, D m =3.9 (3) (pycnometry), D x =4.09 g cm -3 , λ(Ag Kα)=0.5608 A, μ=108.14 cm -1 , F(000)=344, T=296 K, R=0.049, wR=0.053 for 2193 reflections. The first structural investigation on a pyroarsenate is reported

Synthesis and structure determination of a 2D open-framework zincophosphate templated by cyclohexylamine molecules

The synthesis and crystal structure of a new bidimensional zincophosphate (ZnPO) are reported. Zn2(HPO4)2Cl2·2NC6H14 crystallizes in the monoclinic space group P21/a (n°14) with a = 8.830(3) Å, b = 9.278(3) Å, c = 26.950(9) Å, β = 90.74(3)°, V = 2207.7(1) Å3 and Z = 4. This new material consists of a 2D open-framework of corner sharing ZnO3Cl and PO3OH tetrahedra alternating with planes of protonated cyclohexylamine molecules (NC6H14)+. The organic molecules are interconnected to the framework through hydrogen bonds.

4-Amino­pyridinium trans-diaqua­dioxalatochromate(III) monohydrate

In the non-centrosymmetric structure of the title compound, (C5H7N2)[Cr(C2O4)2(H2O)2]·H2O, the CrIII ion has a slightly distorted octahedral coordination environment defined by two chelating oxalato ligands in equatorial positions and two water molecules in axial positions. An extensive three-dimensional network of hydrogen bonds involving all the water molecules, the 4-aminopyridinium cation and some of the oxalate O atoms contributes to the stabilization of the structure. π–π interactions between adjacent pyridine rings provide additional stability of the crystal packing, with a closest distance between pyridine mean planes of 3.613 (1) Å.

trans-Dichlorido(1,4,8,11-tetra­azacyclo­tetra­deca­ne)manganese(III) tetra­fluorido­borate

In the title manganese(III) complex, [MnCl2(C10H24N4)]BF4 or trans-[MnCl2(cyclam)]BF4 (cyclam is the tetradentate amine ligand 1,4,8,11-tetraazacyclotetradecane), the MnIII ions occupy the center of a distorted octahedron coordinated by all four ligand nitrogen donors in the macrobicyclic cavity and two chloride ions occupy the axial positions. Intramolecular hydrogen bonding involving the coordinated chloride ions and the hydrogen atoms of the cyclam ligand is observed. Intermolecular hydrogen bonding involving the tetrafluoridoborate anion and hydrogen atoms of the cyclam ligand leads to an infinite one-dimensional chain along the a axis. The tetrafluoridoborate and inorganic units are linked by N—H⋯F hydrogen bonds. The structure may be compared with those of analogous compounds [MnCl2(cyclam)]ClO4 and [Mn(CN)2(cyclam)]ClO4.

Synthesis and structure determination of a new layered zincophosphate : [H2N2C6H16]0.5[Zn2(PO4)(HPO4)(H2O)].H2O

The synthesis and crystal structure of a new microporous zincophosphate are described. [H2N2C6H16]0.5[Zn2(PO4)(HPO4)(H2O)]·H2O crystallizes in the triclinic space group P1¯ with a = 8.822(4), b = 9.236(4), c = 8.451(3) Å, α = 67.19(3), β = 91.32(3), γ = 111.10(3)°, V = 586.7(4) Å3 and Z = 2. This new material consists of infinite two-dimensional anionic layers alternated with planes containing organic diprotonated templates, N, N, N′, N′-tetramethylethylenediamine [H2N2C6H16]2+ molecules. The framework structure is built up of ZnO4, ZnO3OH2, PO4, and PO3OH tetrahedra, linked through oxygen vertices. The presence of terminal OH2 and OH groups, leads to an open structure containing four- and eight-rings. The organic molecules are interconnected to the framework through hydrogen bonds.

Structure cristalline du paraphenolammonium dihydrogenophosphate

(1–4, HOC6H4NH3)H2PO4, Mr = 206.98, Orthorhombic, P212121, a=6.155(2), b=7.514(3), c=18.704(7)A, V=865.9(1)A3, Z=4, Dm=1.57, Dx=1.59gcm−3, μ= 3.157cm−1, T=298K, R=0.037 (wR=0.027) for 868 independent reflections. The structure was determined by single crystal X-Ray diffraction. It consists of an alternate stacking of (H2PO4)− tetrahedra sheets and (HOC6H4NH3)+ cation sheets. The (H2PO4)− groups are associated to forminfinite chains (H2PO4)n with internal P-P distances of 4.554(1)A, and are connected to the organic planes thanks to strong hydrogen bonds.

Synthesis and structural characterization of the dinuclear tetrakis(guanidino) bis(2-cyanoguanidine)dicopper(II) complex

The synthesis and crystal structure of a new dinuclear complex Cu2(C2H4N4)2 (CH3N3)4 are reported. It crystallizes in the monoclinic system of space group P21/c, with a = 8,459(1) Å, b = 15,481(3) Å, c = 8,714(2) Å, β = 110,60(1)°, and Z = 2. The centrosymmetric molecular structure of Cu2(C2H4N4)2(CH3N3)4 comprises a tetrakis(guanidino)-bridged dinuclear copper(II) core with axially located cnge moities.

LiCo2As3O10: une nouvelle structure à tunnels inter­connectés

The title compound, lithium dicobalt(II) triarsenate, LiCo2As3O10, was synthesized by a solid-state reaction. The As atoms and four out of seven O atoms lie on special positions, all with site symmetry m. The Li atoms are disordered over two independent special (site symmetry -1) and general positions with occupancies of 0.54 (7) and 0.23 (4), respectively. The structure model is supported by bond-valence-sum (BVS) and charge-distribution (CHARDI) methods. The structure can be described as a three-dimensional framework constructed from bi-octahedral Co2O10 dimers edge-connected to As3O10 groups. It delimits two sets of tunnels, running parallel to the a and b axes, the latter being the larger. The Li+ ions are located within the intersections of the tunnels. The possible motion of the alkali cations has been investigated by means of the BVS model. This simulation shows that the Li+ motion appears to be easier mainly along the b-axis direction and that this material may possess interesting conduction properties.

(Na0.38,Ca0.31)MgFe2P3O12

The structure of sodium calcium magnesium iron phosphate, (Na0,38,Ca0,31)MgFe2P3O12, consists of an [MgFe2(PO4)3]− framework, built up by chains of edge-sharing (FeO6–FeO6–MgO6) octahedra running along the [\overline 101] direction. The chains are linked together via the common corners of phosphate tetrahedra to form sheets parallel to the ab plane. Adjacent sheets are also connected through PO4 tetrahedra, thus giving rise to an open framework with two different kinds of channels where the Na+ and Ca2+ cations are located.