| Summary: | Inorganic framework materials, with structures based on arsenate As04 tetrahedra and a variety of additional trigonal, tetrahedral or octahedral units have been synthesised by hydrothermal methods. The framework topologies of these materials have been characterised by single crystal X-ray diffraction; additional techniques, including thermogravimetric analysis and SQUID magnetoinetry, have been used to assess properties ofsome materials. Iron arsenates with 2D and 3D framework topologies are reported; these include structures templated by piperazine; 1,4-diaminobutane, DABCO, Fe2As207·2H20 and LiFeAs040H. The boron arsenic system has been investigated using a molten salt technique and a variety of alkali metal templates. A total of ten boroarsenate materials have been characterised, including [Cs2CBAs030H)s(As04)2] [(CsCI4)]CI, which is templated on both anions and cations and a family of materials XBAs04F ex = Cs, Rb, NHt). Hydrothermal techniques have been used to produce arsenate frameworks in combination with molybdenum, zinc and scandium. Two 'zinc arsenate materials with new framework topologies have been synthesised; a chiral framework with 16-ring channels and a 2D layer framework, both with caesium templates. Five scandium arsenate frameworks have been synthesised and are characterised; three have the same basic framework structure but with differing amine templates. Further new compounds have been synthesised by evaporating solutions of ainines with metal chloride or arsenate covnter-ions; these include three arsenate DABCO structures and a related phosphate DABCO material. Zinc chloride, cobalt chloride and hydrated manganese chloride salts with piperazinium counter-ions were also synthesised. Hydrothermal syntheses with vanadium reagents resulted in the formation of five new structures - a vanadium arsenate; a vanadium oxalate; a nickel vanadate cluster cap'ped by 2,2bipyridyl and isostructural nickel and cobalt metavanadates, NiV20 6·H20 and CoV206·H20. Powder neutron diffraction was used to show the isostructural,materials possessed differing magnetic cells. During investigations into copper arsenate framework materials, four new copper halide coordination polymers were discovered. Two materials with tetramethylammonium (TMA) templates - CU2Br3(TMA) and CU2I3(TMA) - and a DABCO templated structure CU2Ch(DABCO) share a common stoichiometry but were shown to possess different structural motifs. A fourth material discovered, CU7I7(DABCOhs, forms a· complex 3D organic-inorganic hybrid framework.
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