Formation of ladders from R(4)4(8) and R(6)6(12) rings in 8-hydroxyquinolinium chloride monohydrate: comparisons with the supramolecular arrangements in related salts.

Molecules of the title compound, C9H8NO+.Cl-.H2O, are linked into two rings by strong hydrogen bonding via the free water molecules and the Cl- anions. The two hydrogen-bonded rings are joined to give a corrugated chain along [001]. Comparisons with other 8-hydroxyquinoline-based salts are also presented, highlighting similar ring structures in a 1:1 salt with Kemp's triacid (r-1,c-3,c-5-trimethylcyclohexane-1,3,5-tricarboxylic acid) and in 8-hydroxy-1-methylquinolinium chloride monohydrate.