Hydrogen bonding in quinolinium-4-carboxylate trihydrate.

The previously undescribed title substance, C10H7NO2.-3H2O, crystallized in the centrosymmetric space group P1 with one zwitterionic organic molecule and three water molecules in the asymmetric unit. One N-H...O and six O-H...O hydrogen bonds are present in this structure, with donor-acceptor distances ranging from 2.607(2) to 2.931(3) A. The H atoms in these hydrogen bonds are ordered. The hydrogen bonds generate a two-dimensional network. Structural comparisons are made with quinolinium-4-carboxylate dihydrate.