Structural stability index of heteropoly- and isopolyanions-IV. Application to site-vacant Keggin polyanions, mixed-type Keggin polyanions, some molybdo- and tungsto-vanadates and Jeannin-type polyanion

Abstract

The theory of structural stability, being based on the number of closed loops per MO6 octahedral unit in the polyanion-cage, has been applied to a variety of heteropoly- and isopoly-compounds with previously unreported structures. The discussion includes the prediction of the structure of lacunary Keggin heteropoly-compound, Cs7Na2[PW10O37]·8H2O, recently obtained by Knoth and Harlow, the reinvestigation of mixed-type Keggin polyanions, [SiW9Co3(H2O)3O37]10- and [SiW11CoO39]6-, recently prepared by Pope's group, the interpretation of chemical behaviours of some molybdo- and tungsto-vanadates, the structural stabilities of Jeannin-type [As2W21O69(H2O)]6- polyanion and its related compounds, and some remarks on Weakley-type [X(W5O18)2]n- polyanions and Flynn-Stucky-type [X(Nb6O19)2]n- complexes belonging to the hybrid-complex of polyanion. © 1985.