Synthesis and Characterization of Cu(II) Substituted Hexa Tungstate and Molybdate of the Anderson Type Anion [Xⁿ⁺M₆O₂₄]^-(12-n)

Abstract

Sodium salts of copper substituted heteropoly compounds having molecular formula Na₁₀[Cu^IIW^VI₆O₂₄].22H₂O(1) and Na₁₀[Cu^IIMo^VI₆O₂₄]. 19H₂O(2) analogous to the Anderson type anion [Xⁿ⁺M₆O₂₄]─^(12-n) were synthesized according to the literature method. Compound(1) was synthesized from aqueous acidic solution containing sodium tungstate and copper chloride and compound(2) from sodium molybdate and copper chloride solution. The elemental analyses show 1:6 atomic ratio of the heteroatom to the addenda in both the compounds. The IR spectra for both the compounds are in good agreement with the reported formulae. A small deviation in IR spectra are observed than that established for Keggin anions. CuO₆ acts as hetero group which replaces MO₆ (M=W or Mo) from the Anderson structure. The thermal analyses of the compounds show the loss of the peripheral water molecules. The molecular weight of the compound (1) and (2) have been found as 2212.5 and 1600.5 respectively.