A new type of mixed anionic framework in microporous rubidium copper vanadyl(V) phosphate, Rb2Cu(VO2)2(PO4)2

In dirubidium copper bis[vanadyl(V)] bis(phosphate), Rb2Cu(VO2)2(PO4)2, three different oxo complexes form an anionic framework. VO5 polyhedra in a trigonal bipyramidal configuration and PO4 tetrahedra share vertices to form eight‐membered rings, which lie in layers perpendicular to the a axis of the monoclinic unit cell. Cu atoms at centres of symmetry have square‐planar coordination and link these layers along [100] to form a three‐dimensional anionic framework, viz. [Cu(VO2)2(PO4)2]∞2−. Intersecting channels in the [100], [001] and [011] directions contain Rb+ cations. Topological relations between this new structure type and the crystal structures of A(VO2)(PO4) (A = Ba, Sr or Pb) and BaCrF2LiF4 are discussed.