title: 4-Carboxy-pyridazin-1-ium chloride.
abstract: The structure of the title compound, C(5)H(5)N(2)O(2) (+)·Cl(-), is composed of chloride anions and 4-carboxy-pyridazin-1-ium cations. Chloride anions bridge the cations via O-H⋯Cl and N-H⋯Cl hydrogen bonds to form ribbons. The latter, linked by van der Waals forces with lengths in the range 3.254 (2)-3.497 (2) Å, form coplanar layers. Very weak inter-actions operate also between adjacent layers, as indicated by their spacing of 3.339 (1) Å.
authors.affiliation: Institute of Nuclear Chemistry and Technology, ulica Dorodna 16, 03-195 Warszawa, Poland.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Starosta
authors.forename: Janusz
authors.initials: J
authors.lastname: Leciejewicz