title: 3,4-Di-amino-pyridinium hydrogen malonate.
abstract: In the title salt, C5H8N3 (+)·C3H3O4 (-), the 3,4-di-amino-pyridinium cation is almost planar, with an r.m.s. deviation of 0.02 Å. The conformation of the hydrogen malonate anion is stabilized by an intra-molecular O-H⋯O hydrogen bond, which generates an S(6) ring. In the crystal, N-H⋯O hydrogen bonds link cations and anions into layers parallel to the ab plane.
authors.affiliation: Kathmandu University Budol, Dhulikhel 45200, Nepal.
authors.forename: Surendra
authors.initials: S
authors.lastname: Thapa
authors.forename: Sergiu
authors.initials: S
authors.lastname: Draguta
authors.forename: Bhupinder
authors.initials: B
authors.lastname: Sandhu
authors.forename: Mikhail Yu
authors.initials: MY
authors.lastname: Antipin
authors.forename: Tatiana V
authors.initials: TV
authors.lastname: Timofeeva