Hydrothermal Syntheses, Crystal Structure And Properties Of Polyoxometalates Based On Arsenic Heteroatom

In the paper, on the basis of molecular design and assembly conceptions, adopting simplematerials such as （NH₄）6Mo7O₂₄·₄H₂O, Na₂MoO₄·₂H₂O, NaAsO₂and As₂O₃or classicalheteropolymolybdate precursor Na9[α-AsW9O33]·19H₂O, under hydrothermal conditions or theconventional aqueous methods, several of novel organic-inorganic polyoxometalates derivativesbased on arsenomolybdates or arsenotungstates were obtained by controling reaction conditionssuch as pH value, temperature, time, concentration and reactant stoichiometry. These complexeswere charactered by X-ray crystallography, IR, UV spectroscopy, thermal properties, XRD、XPS、EDX or magnetic analyses.1. Seven novel organic-inorganic compounds based on different arsenomolybdate fragments:[Cu₄（en）₄O₂（H₂O）₂][H₂As^V₂Mo₆O₂6]（1）,[Cu（en）₂（H₂O）]₄[Cu（en）₂（H₂O）₂]{[Cu（phen）（en）][AsIIIAs^VMo^VI9O₃₄]₂}（₂）,[H₂en][Ni（en）₂][Ni（en）₂（H₂O）][AsIIIAs^VMo9O₃₄]·3H₂O（3）,（H₂en）[Cu（en）₂][（CuO₆）Mo₆O₁8（As₃O₃）₂]·10H₂O （₄）, H（NH₄）₃[（NiO₆）Mo6O₁8（As₃O₃）₂]·3H₂O （5）,（NH₄）₇[AsMo8O30]（6） and {[Co（C₈H₇N₃）（H₂O）][Co（C₈H₇N₃）]}₂[HAs^VMo^V6Mo^VI6O₄0]·₂.5H₂O （7） have been successfully under hydrothermal conditions.1is a one-dimensional （1D） infinite chain built by A-[H₄–₂As^V₂Mo6O₂6]units and the rare[Cu₄（en）₄O₂（H₂O）₂]₄+cations.₂and3are constructed from the monocapped trivacant Keggin[A-α-AsIIIAs^VMo^VI69O₃₄]units.₄and5are based on the dicapped-Anderson type[（MO₄6）Mo6O₁8（As₃O₃）₂]fragments.6is based on the [AsMo78O30] polyoxoanion and7is thefirst organic-inorganic compound that constructed from the ε-[HAs^VMo^V6Mo^VI6O₄0]8–units andtransition-metal complexes.₂. Three sandwich-type arsenotungstates based on the trivacant Keggin-type [B-α-AsW9O₃₄]9and [B-α-AsW9O33]9building block:（H₂en）{[Cu（en）₂]₂[Cu₂（en）₂Cu₄（H₂O）₂](B-α-AsW9O₃₄)₂}·5H₂O （8）,[H11（C3H6N6）1₂]（AsO₂）{[Co₄（H₂O）₂](B-α-AsW9O₃₄)₂}·9H₂O（9） and H8[NaCu5Cl（H₂O）₃（B-α-AsW9O33）₂]·₂₄H₂O （10） were sysnthesized successfully through hydrothermal synthesis method or the conventional aqueous methods. Compound8showsan infinitely extended2-D network via Cu–O–W bridges.