Crystal structure of calcium (cyano)monohydroethylenediaminetetraacetatocobaltate(III) hexahydrate

The crystal structure of a complexonate of the composition Ca[CoHEdta(CN)]2·6H2O was determined by x-ray diffraction (CAD-4 diffractometer, MoKα radiation, 1883 reflections, the heavy-atom method, anisotropic refinement to R=0.026). The crystals are monoclinic, a=19.021(3), b=7.446(1), and c=12.646(2) A; β=107.43(1) deg.; sp. gr. P2/c; and Z=2. The Co atom is octahedrally coordinated with the pentadentate HEdta3- ligand and the CN- group. An anionic [CoHEdta(CN)]- complex contains four metallocycles--an ethylenediamine cycle and three glycinate cycles. A distorted centrosymmetric octahedral coordination of the Ca atom is formed by two water molecules and four carbonyl oxygen atoms from different complexes, which results in the formation of the layer structure. The uncoordinated acetate arm and water molecules are involved in a hydrogen-bond system, which both stabilizes and crosslinks the layers