Poly[bis(2,2'-bipyridine-κN,N')heptadeca-μ-oxido-tetraoxidodicopper(II)divanadate(IV)hexavanadate(V)].

In the title complex, Cu(2)V(8)O(21)(2,2'-bpy)(2) (bpy = bipyridine, C(10)H(8)N(2)), the asymmetric unit contains four independent V atoms briged by 11 O atoms, one of which lies on an inversion center, and a Cu(2,2'-bpy) unit. Three V atoms in the polyoxoanion exhibit distorted tetra-hedral coordination geometries while the fourth V atom adopts a trigonal-bipyramidal geometry. The Cu atom adopts a square-pyramidal geometry being coordinated by two nitro-gen donors of a 2,2'-bpy ligand, and three bridging O atoms which are linked with V atoms. The V(8) polyoxoanion is connected to Cu(2,2'-bpy) cations, resulting in a two-dimensional layer structure extending parallel to (010). C-H⋯O hydrogen bonding consolidates the structure.