(C₄H₁₄N₂)₂[Mo₈O₂₆]·2H₂O: a new molybdate salt

Crystals of the title compound, 2-(dimethyl­ammonio)­ethanaminium hexa­cosa­oxaocta­molybdate(VI) dihydrate, containing extended chains constructed from centrosymmetric octa­molybdate anions, were grown under mild hydro­thermal conditions in the presence of N,N-dimethyl­ethylenediamine. An extensive hydrogen-bonding network helps stabilize the crystal structure.