Crystal structure of ammonium (3,5-di­chloro­phen­oxy)acetate hemihydrate

In the structure of the title hydrated salt, NH(4) (+)·C(8)H(5)Cl(2)O(3) (−)·0.5H(2)O, where the anion derives from (3,5-di­chloro­phen­oxy)acetic acid, the ammonium cation is involved in extensive N—H⋯O hydrogen bonding with both carboxyl­ate and ether O-atom acceptors giving sheet structures lying parallel to (100). The water mol­ecule of solvation lies on a crystallographic twofold rotation axis and is involved in intra-sheet O—H⋯O(carboxyl­ate) hydrogen-bonding inter­actions. In the anion, the oxoacetate side chain assumes an antiperiplanar conformation with the defining C—O—C—C torsion angle = −171.33 (15)°.