L-Aspartic acid nitrate–L-aspartic acid (1/1)

In the title compound, C4H8NO4+·C4H7NO4·NO3−, the cation and neutral mol­ecule are connected by an asymmetric hydrogen bond. The cation, residue 1, exists in a gauche I conformation, whereas the neutral mol­ecule, residue 2, exhibits a gauche II conformation. A syn–syn orientation is also observed in this structure and residue 1 is involved in a straight (S1) head-to-tail sequence. The structure is stabilized by both inter- and intramolecular N—H⋯O hydrogen bonding.