Tetrakis(2,6-dimethylpyridinium) dihydrogen decavanadate dihydrate

The structure of the title compound, (C7H10N)(4)[H2V10O28]-2H(2)O, was solved from a non-merohedrally twinned crystal (ratio of twin components similar to 0.6:0.4). The asymmetric unit consists of one-half decavanadate anion (the other half completed by inversion symmetry), two 2,6-dimethylpyridinium cations and one water molecule of crystallization. In the crystal, the components are connected by strong N-H center dot center dot center dot O and O-H center dot center dot center dot O hydrogen bonds, forming a supramolecular chain along the b-axis direction. There are weak C-H center dot center dot center dot O interactions between the chains.