Bis[1-(isopropylideneamino)guanidinium]bis(3-nitrobenzoate) monohydrate

The asymmetric unit of the title salt hydrate, 2C(4)H(11)N(4)+center dot 2C(7)H(4)NO(4)(-)center dot H2O, comprises two independent 1-(isopropylideneamino)guanidinium cations, two independent 3-nitrobenzoate anions and a water molecule of crystallization. There are minimal geometric differences between the two planar [maximum deviations 0.061 (2) and 0.088 (2) angstrom] cations, and between the two almost planar anions [C-C-C-O and C-C-N-O torsion angles of 0.3 (3) and 11.1 (4)degrees, respectively in the first anion and -173.7 (2) and -0.1 (4), respectively in the second anion]. Extensive O-H center dot center dot center dot O and N-H center dot center dot center dot O hydrogen bonding between all components of the structure leads to the formation of a two-dimensional array with an undulating topology in the bc plane.