Synthesis and Structures of Two New Molybdophosphates

A one dimension solid and a two dimension solid consisting of polyoxoanions bridged by {CoO 3N 2} and {CoO 4} groups respectively have been synthesized by the hydrothermal method and structurally characterized by X Ray crystallography. Each structure has the [(PO 4) 4Mo 6O 15 ] 12- cluster that is commonly observed in many molybdophosphates. In compound 1, [(PO 4) 4Mo 6O 15 ] 12- clusters are linked by {CoO 3N 2} groups to form a chain like structure, and the chains are hydrogen bonded into a network. Compound 2 is a layer structure with channnels constructed from [(PO 4) 4Mo 6O 15 ] 12- clusters and {CoO 4} groups, the organic molecules and the lattice water molecules are distributed disorderly in the interlamellar region and form strong hydrogen bonds with inorganic framework. The IR and the fluorescent spectra were investigated and discussed.

Hydrothermal Synthesis and Crystal Structure of Iron Molybdophosphate Fe[Mo_6O_(12)(OH)_3(H_2PO_4)(HPO_4)_2(PO_4)]_2- [Fe(2,2′-bipy)(H_2O)_2]_2[Fe(2,2′-bipy)_3]_2·6H_2O

A molybdenum（V） phosphate supported by iron coordination complexes, Fe[Mo6O12（OH）3（H2PO4）（HPO4）2（PO4）]2[Fe（2,2′-bipy）（H2O）2]2[Fe（2,2′-bipy）3]2·6H2O （bipy = 2,2′-bipyridine） 1, has been synthesized by hydrothermal synthesis and characterized. The title complex crystallizes in the monoclinic system, space group P21/c with a = 14.0005（8）, b = 25.5229（12）, c = 17.9956（9） A, β = 103.470（2）°, V= 6253.5（6） A^3, Z= 2, Mr = 4114.03, Dc = 2.185 g/cm^3, F（000） = 4040, μ = 1.931 mm^-1, R = 0.0438 and wR = 0. 1168. The structure of the title polyoxometalate anion is based on a centrosymmetrical cluster Fe[Mo6O2（OH）3（H2PO4）（HPO4）2（PO4）]2 supported by two [Fe（2,2′-bipy）（H2O）2] subunits. The 2D network is formed through intermolecular hydrogen bonds.

Syntheses,Crystal Structures and Electrochemical Properties of Two Molybdophosphates

Two molybdophosphate compounds,[Ni（bim）3]2[H2P2Mo5O23]·2H2O 1 and [Zn（bpy）2]2[Zn（bpy）（H2O）]2Zn[Mo6O12（OH）3（HPO4）4]2·9H2O 2 （bim = 2,2＇-biimidazole,bpy = 2,2＇-dipyridyl）,have been synthesized under hydrothermal conditions and structurally characterized by elemental analysis,TG,and IR. The single-crystal X-ray analysis exhibits that 1 consists of one [H2P2Mo5O23]4-,two [Ni（bim）3]2＋ cations and two lattice water molecules,while 2 is constructed from one sandwich-type [ZnP4Mo6] anion modified by four Zn-bpy complexes and nine lattice water molecules. The electrochemical behaviors of compounds 1 and 2 have been studied in detail based on solid bulk modified carbon paste electrodes of compound （CPEs）.

One inorganic–organic hybrid derived from reduced molybdophosphate and trinuclear cadmium(II) fragment

One new polyoxometalate （POM）-based inorganic-organic hybrid [Cdn3~HPO4）（Hbpp）（H20）2]{CdII[P4_ Mo6028H3.s（OH）312}.（H4tpb）.7H20 （1） （bpp = 1,3-bis-（4-pyridyl）propane, tpb = 1,2,4,5-tetra（4-pyridyl）- benzene） constructed from reduced molybdophosphate [P4Mo6028H3.5（OH）3]s＇5- （P4Mo6）, trinuclear Cdn-phosphate-Hbpp fragment and protonated tpb has been hydrothermally synthesized and structurally characterized by IR, elemental analyses and single crystal X-ray diffraction. The complex 1 crystallizes in the monoclinic system with the space group P21]c and cell parameters of a=15.672（12）A, b=23.839（19）A, c=27.654（2）,~, fl=115.850（10）~, V=9297.9（12） ~3, Z=4, R1 ~0.0534 and wR2 ~0.1135. In complex 1, the P4Mo6 units are bridged by CdII ions to form the classic sandwich-type [Cd（P4Mo6）2] dimers, which are further connected into a two dimensional network via the trinuclear Cdn subunits. The tpb is synthesized in situ from the bpp ligands and connects the adjacent 2D layers into a 3D supramolecular framework through hydrogen bonding interactions. The electrochemical and fluorescent properties of complex 1 have been investigated.

One Dimensional Iron Molybdophosphate Anionic Chains with Different Structural Arrangements Reflecting a Flexibility Character

Structural comparison of a new compound [（bpp）3H6]Fe2ⅢFe2ⅡMo24Ⅴ（H2PO4）8（HPO4）4（PO4）4O48（OH）12·（H2O）4·2H2O（1）[bpp=1,3-di（4-pyridyl）propane] with our previously reported two compounds [（bpy）3FeⅡ]3·Fe2ⅢFe2ⅡMo24Ⅴ（H2PO4）8（HPO4）4（PO4）4O48（OH）12（H2O）4·12H2O（2） and [（bpy）3FeⅡ]2FeⅡFeⅢMo12Ⅴ（H2PO4）2（H2-xPO4）.（H1＋xPO4）（HPO4）2（PO4）2O24（OH）6（H2O）2·9H2O（x=0-1）（3）（bpy=2,2＇-bipyridine）,which all exhibit one-dimensional mixed-valence iron molybdophosphate anionic chains constructed by alternating connection of FeⅢ ions and magic [FeⅡ（Mo6P4O31）2] units,reveals that the non-hydrogen atomic ratios of Mo∶Fe∶P∶O within the polymeric anionic chains are the same for all the three compounds,while the polymeric anionic chains of the different compounds bear different numbers of negative charges.And therefore there exist different numbers of counter cations per {Fe2Ⅲ[Fe2Ⅱ（P16Mo24ⅤO124）]} unit found in the titled compounds.It discloses that not only are the spatial assembling of counter cations and polymeric inorganic chains of three compounds quite different,but also the O-FeⅢ-O bond angles and FeⅢ-O bond lengths of the three different inorganic chains exhibit small differences.What is more important is that such small changes in bond length and bond angle in the assemblage of FeⅢ-O bonds lead to the considerable fluctuations of inorganic chains in their structural conformation within the three compounds,reflecting an interesting phenomenon of＂flexibility＂ in the pure inorganic one dimensional mixed-valence iron molybdophosphate chains.

Synthesis, Characterization and Ion Exchange Properties of a New Composite of Inorganic Ion Exchanger： Polyacrylonitrile Cerium（IV） Molybdophosphate

In this work, the synthesis of the composite of cerium（IV） molybdophosphate （CMP） and polyacrylonitrile （PAN） was reported （CMP-PAN）. The material has been characterized by elemental and spectral （FT-IR）, X-ray and thermal （TGA） analysis. Also the size analysis of the composite was done by scanning electron microscopy （SEM）. Its chemical stability in acidic, basic and saline solutions and radiation stability up to 100 kGy total expose dose were assessed. Whereas the synthesized composite has ion exchange properties, its ion exchange capacity and behavior toward several metal ions were also investigated. Further, the distribution coefficients of the metal ions were calculated. Finally, the ability of the synthesized CMP-PAN composite for the decontamination of low level liquid waste （LLLW） was investigated.

Preparation and Characterization of Heteropoly Octadecamolybdodiphosphates

Heteropoly molybdophosphates with general formula M(?)P2Mo18O62 ·xH2O, where M = H+, K+, NH4+, Ca2+, Co2+, Ni2+, Cu2+, Zn2+ and Ag+, were prepared and characterlzed by elemental analysis, IR and UV spectrometry and thermal analysis. The solubilities of the compounds were examined. The IR spectra show that the countercations and the crystallization water have an influence upon the vibration frequencies of vMo-Oc and vMo-Oc-Mo·In the UV spectra, the charge-transfer bands are assigned to e→e and e→b2 transition. All the compounds decompose at 328-534℃.