An Experimental

R factor = 0.068; wR factor = 0.189; data-to-parameter ratio = 12.3. In the structure of the title salt, 2C7H10N +C8H2Cl2O42H2O, the two benzylaminium anions have different conformations, one being essentially planar and the other having the side chain rotated out of the benzene plane [minimum ring to side-chain C—C—C—N torsion angles = 3.6 (6) and 50.1 (5), respectively]. In the 4,5-dichlorophthalate dianion, the carboxylate groups make dihedral angles of 23.0 (2) and 76.5 (2) with the benzene ring. In the crystal, aminium N— H O and water O—H O hydrogen-bonding associations with carboxylate O-atom acceptors give a two-dimensional duplex sheet structure which extends along the (011) plane. Weak – interactions are also present between the benzene ring of the dianion and one of the cation rings [minimum ring centroid separation = 2.749 (3) Å]. Related literature For the crystal structures of some 1:1 Lewis base salts of 4,5