L-Asparaginium nitrate

The title compound, C₄H₉N₂O₃⁺·NO₃^-, crystallizes with two asparaginium cations and two nitrate anions in the asymmetric unit. In both asparaginium residues, protonation take place at the carboxyl O atom cis to the amine group. Cation I exists in a trans conformation, whereas cation II exhibits a gauche I conformation. A straight head-to-tail sequence is observed for one of the asparaginium cations. The crystal structure is stabilized by inter- and intra­molecular hydrogen bonding.