K₂MoO₂(MoO₂As₂O₇)₂

Diotassium molybdenyl bis[molybdenyl diarsenate(4−)] is built up from As₂O₇ groups and MoO₆ corner-sharing octahedra to form a three-dimensional framework with intersecting tunnels where the K⁺ ions reside. Structural relationships with the frameworks of the mixed diphosphates CsHMoO₂P₂O₇ (one dimensional), Na₂VOP₂O₇ (two dimensional), and β-BaV₂(P₂O₇)₂ (three dimensional) are discussed.

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