1,1'-Diethyl-4,4'-bipyridine-1,1'-diium bis(1,1,3,3-tetracyano-2- ethoxypropenide): multiple C-H⋯N hydrogen bonds form a complex sheet structure

In the title salt, C₁₄H₁₈N₂²⁺·2C₉H₅N₄O⁻, the 1,1′-diethyl-4,4′-bipyridine-1,1′-diium dication lies across a centre of inversion in the space group P2₁/c. In the 1,1,3,3-tetracyano-2-ethoxypropenide anion, the two independent –C(CN)₂ units are rotated, in conrotatory fashion, out of the plane of the central propenide unit, making dihedral angles with the central unit of 16.0 (2) and 23.0 (2)°. The ionic components are linked by C—H⋯N hydrogen bonds to form a complex sheet structure, within which each cation acts as a sixfold donor of hydrogen bonds and each anion acts as a threefold acceptor of hydrogen bonds.