The crystal structure and doublet emission properties of trans-[Cr(NH3)2(cyclam)](ClO4)Cl2

Crystal structure of cis-di-chlorido-(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4N)chromium(III) (oxalato-κ2O1,O2)(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4N)chromium(III) bis(perchlorate) from synchrotron data

In the asymmetric unit of the title compound, [CrCl2(C10H24N4)][Cr(C2O4)(C10H24N4)](ClO4)2 (C10H24N4 = 1,4,8,11-tetra-aza-cyclo-tetra-decane, cyclam; C2O4 = oxalate, ox), there are two independent halves of the [CrCl2(cyclam)]+ and [Cr(ox)(cyclam)]+ cations, and one perchlorate anion. In the complex cations, which are completed by application of twofold rotation symmetry, the CrIII ions are coordinated by the four N atoms of a cyclam ligand, and by two chloride ions or one oxalate bidentate ligand in a cis arrangement, displaying an overall distorted octa-hedral coordination environment. The Cr-N(cyclam) bond lengths are in the range of 2.075 (5) to 2.096 (4) Å while the Cr-Cl and Cr-O(ox) bond lengths are 2.3358 (14) and 1.956 (4) Å, respectively. Both cyclam moieties adopt the cis-V conformation. The slightly distorted tetra-hedral ClO4- anion remains outside the coordination sphere. The supra-molecular architecture includes N-H⋯O and N-H⋯Cl hydrogen bonding between cyclam NH donor groups, O atoms of the oxalate ligand or ClO4- anions and one Cl ligand as acceptors, leading to a three-dimensional network structure.

Crystal structure of trans-diammine(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ(4) N)chromium(III) tetra-chlorido-zincate chloride monohydrate from synchrotron data

The asymmetric unit of the title complex salt, [Cr(C10H24N4)(NH3)2][ZnCl4]Cl·H2O, is comprised of four halves of the Cr(III) complex cations (the counterparts being generated by application of inversion symmetry), two tetra-chlorido-zincate anions, two chloride anions and two water mol-ecules. Each Cr(III) ion is coordinated by the four N atoms of the cyclam (1,4,8,11-tetra-aza-cyclo-tetra-deca-ne) ligand in the equatorial plane and by two N atoms of ammine ligands in axial positions, displaying an overall distorted octa-hedral coordination environment. The Cr-N(cyclam) bond lengths range from 2.0501 (15) to 2.0615 (15) Å, while the Cr-(NH3) 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 [ZnCl4](2-) anions have a slightly distorted tetra-hedral shape. In the crystal, the Cl(-) anions link the complex cations, as well as the solvent water mol-ecules, through N-H⋯Cl and O-H⋯Cl hydrogen-bonding inter-actions. The supra-molecular 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 mol-ecules, Cl(-) anions or Cl atoms of the [ZnCl4](2-) anions as acceptors, leading to a three-dimensional network structure.