1-Methyl-4-[(1E,3E)-4-phenyl­buta-1,3-dien­yl]pyridinium iodide monohydrate

The asymmetric unit of the title compound, C(16)H(16)N(+)·I(−)·H(2)O, contains two 1-methyl-4-{[(1E,3E)-4-phenyl­buta-1,3-dien­yl]}pyridinium cations, two iodide ions and two solvent water mol­ecules. The cation is twisted slightly, the dihedral angle between the pyridinium and the phenyl rings being 10.68 (18)° in one mol­ecule and 18.9 (3)° in the other. The two water mol­ecules are disordered over three positions with site-occupancy ratio of 0.9/0.7/0.4. In the crystal packing, the cations are arranged into ribbons along the b axis with the iodide ions and water mol­ecules located between adjacent cations. The cations are linked to the iodide ions and water mol­ecules by weak C—H⋯I and C—H⋯O inter­actions, respectively. These inter­actions together with O—H⋯I hydrogen bonds link the mol­ecules into a two-dimensional network parallel to the bc plane. π⋯π inter­actions with a centroid–centroid distance of 3.669 (2) Å are also observed.