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[NH4]12[(MoO2)2O(HPO4)2]4[PO4]X, X = Cl, Br—new porous layer molybdenophosphates with embedded multiple anionic and cationic guests
No full textThe compounds [NH4]12[(MoO2)2O(HPO4)2]4[PO4]X, X = Cl, Br are constructed from molybdenophosphate layers of unique topology that are penetrated by channels containing perfectly ordered, alternating ammonium cations and free orthophosphate (PO43-) or halide (Cl-, Br-) anion
A new host for MnO43-: synthesis and characterisation of the NaCaV1-xMnxO4 system
No full textThe incorporation of the intensely coloured charge transfer species MnO43- has been investigated for NaCaVO4. The series of compounds NaCaV1-xMnxO4 (where x = 0, 0.02, 0.04, 0.06, 0.08, 0.1) has been successfully prepared and results in the formation of blue/green coloured powders. A structural characterisation of the materials has been performed and the results are presented. The series is seen to adopt an orthorhombic structure in the space group Cmcm (No.63). On increasing manganese content an overall reduction of the cell volume was observed and the limit of substitution occurs at x 0.08
Cerium(IV) fluoride and fluoride-arsenate frameworks
No full textFive new cerium (IV) fluoride and fluoride–arsenate framework structures have been synthesised hydrothermally using CeF4 as a fluoride source. Cs[Ce2F8[F·H2O]] ( I) consists of layers, formed from linked Ce(F,O)n polyhedra cross-linked by hydrogen bonding that defines large channels containing the caesium ions. [(NH4)5(H2O)2][Ce4(AsO4)6(H2O)F3] ( II), has an open framework structure with large channels filled with NH4+ cations and H2O molecules. Ce[AsO4]F ( III) and Ce[AsO4]F[H2O] ( IV) exhibit two types of bridging (Ce–O–Ce and Ce–F–Ce) bonds between Ce(O,F)n polyhedra, and (NH4)[CeF2(AsO4)] ( V), is isostructural with the previously reported fluoride-phosphate (NH4)[CeIVF2(PO4
Characterisation of four new two-dimensional lithium beryllofluoro-layered compounds
No full textFour new amine-templated materials, containing two-dimensional lithium beryllofluoride sheets of the stoichiometry [LiBeF4](-), have been synthesised under hydrothermal and ambient pressure conditions. [LiBeF4][C6H4(CH3)CH2NH3] (1), [LiBeF4] [C6H4CH2NH3Cl (2), [LiBeF4](2)- [NH3CH2CH2CH2NH3] (3), and [LiBeF4][C6H5CH2CH2CH2NH3] (4) all contain well-separated anionic sheets containing two different topologies with the 'inter-layer' regions comprising of organoamine templating species. Use of the different organoamine templating agents results in compounds possessing very different relative arrangements of the lithium beryllofluoride sheets. The materials crystallise in P-centred orthorhombic and monoclinic cells; for 1 (templating agent: 3-methylbenzylamine) Pca2(1); for 2 (4-chlorobenzylamine) Pbca; for 3 (1,3-diamminopropane) Pccn, and for 4 (3-phenyl-1-propylamine) P2(1)/c. Hydrogen bonding exists between ions situated on the protonated amine groups on the templating species and electronegative fluoride ions, on MF4 tetrahedra (where M = Li and Be)
Synthesis and crystal structures of iron hydrogen phosphates
No full textThree new iron hydrogen phosphate compositions have been synthesised under hydrothermal conditions; Fe(II)2O(HPO4) ( 1), (NH4)3Fe(III)3(HPO4)6 ( 2) and Fe1.34(III)(PO4)OH0.96 ( 3). 1 and 2 have framework structures constructed from FeO6 octahedra and HPO4/PO4 tetrahedra containing cavities; in the case of 2, these are occupied by ammonium cations while in 1 they are cross linked by hydrogen bonding involving the HPO4 groups. Crystals of 3 grow as 30 m octahedral jackstones and this synthetic material adopts the structure from the Lipscombite solid solution. Thermal decomposition of these materials yields simple iron phosphates and the potential of these compounds and their derivatives, formed for example through Li+-ion exchange of NH4+, for battery applications is discusse
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