Poly[(l6-4-amino-3,5,6-trichloro- pyridine-2-carboxylato)aquacaesium]

R factor = 0.021; wR factor = 0.053; data-to-parameter ratio = 13.1. In the structure of the title complex, [Cs(C6H2Cl3N2O2)-(H2O)]n, the caesium salt of the commercial herbicide picloram, the Cs+ cation lies on a crystallographic mirror plane, which also contains the coordinating water molecule and all non-H atoms of the 4-amino-3,5,6-trichloropicolinate anion except the carboxylate O-atom donors. The irregular CsCl4O5 coordination polyhedron comprises chlorine donors from the ortho-related ring substituents of the picloramate ligand in a bidentate chelate mode, with a third chlorine bridging [Cs—Cl range 3.6052 (11)–3.7151 (11) Å] as well as a bidentate chelate carboxylate group giving sheets extending parallel to (010). A three-dimensional coordination polymer structure is generated through the carboxylate group, which also bridges the sheets down [010]. Within the structure, there are intra-unit water O—H Ocarboxylate and amine N— H Npyridine hydrogen-bonding interactions. Related literature For background information on picloram, see: Mullinson (1985); O’Neil (2001). For examples of structures of metal complexes with picloram, see: Smith et al. (1981a,b); O’Reilly et al. (1983). For another structure with caesium cations involving coordinating carbon-bound Cl, see: Levitskaia et al. (2000). For a caesium complex with dipicolinic acid, see: Santra et al. (2011)