Crystal structure of bis­[4-(di­methyl­amino)­pyridinium] aqua­bis­(oxalato)oxidovanadate(IV) dihydrate

The title organic–inorganic hybrid salt, (C(7)H(11)N(2))(2)[V(C(2)O(4))(2)O(H(2)O)]·2H(2)O, shows a distorted octa­hedral coordination environment for the vanadium(IV) atom in the anion (point group symmetry 2), with four O atoms from two symmetry-related chelating oxalate dianions and two O atoms in trans configuration from a coordinating water mol­ecule and a terminal vanadyl O atom. In the crystal, (001) layers of cations and anions alternate along [001]. The anionic layers are built up by inter­molecular O—H⋯O hydrogen bonds involving the coordinating and solvent water mol­ecules. The cationic layers are linked to the anionic layers via N—H⋯O hydrogen bonds between the pyridinium group and the non-coordinating O atoms of the oxalate group. The 4-(di­methyl­amino)­pyridinium cations are also engaged in π–π stacking with their anti­parallel neighbours [centroid-to-centroid distance = 3.686 (2) Å]. Considering all supra­molecular features, a three-dimensional network structure is accomplished.