Crystal structure of trans -diammine(1,4,8,11-tetraazacyclotetradecane-κ 4 N )chromium(III) tetrachloridozincate chloride monohydrate from synchrotron data

The asymmetric unit of the title complex salt, [Cr(C 10 H 24 N 4 )(NH 3 ) 2 ][ZnCl 4 ]Cl·H 2 O, is comprised of four halves of the Cr III complex cations (the counterparts being generated by application of inversion symmetry), two tetrachloridozincate anions, two chloride anions and two water molecules. Each Cr III ion is coordinated by the four N atoms of the cyclam (1,4,8,11-tetraazacyclotetradecane) ligand in the equatorial plane and by two N atoms of ammine ligands in axial positions, displaying an overall distorted octahedral coordination environment. The Cr—N(cyclam) bond lengths range from 2.0501 (15) to 2.0615 (15) Å, while the Cr—(NH 3 ) bond lengths range from 2.0976 (13) to 2.1062 (13) Å. The macrocyclic cyclam moieties adopt the trans -III conformation with six- and five-membered chelate rings in chair and gauche conformations. The [ZnCl 4 ] 2− anions have a slightly distorted tetrahedral shape. In the crystal, the Cl − anions link the complex cations, as well as the solvent water molecules, through N—H...Cl and O—H...Cl hydrogen-bonding interactions. The supramolecular set-up also includes N—H...Cl, C—H...Cl, N—H...O and O—H...Cl hydrogen bonding between N—H or C—H groups of cyclam, ammine N—H and water O—H donor groups, and O atoms of the water molecules, Cl − anions or Cl atoms of the [ZnCl 4 ] 2− anions as acceptors, leading to a three-dimensional network structure.