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Aqua-chloridobis(diphenyl-glyoximato-κN,N')cobalt(III) dihydrate
Parthasarathy Meera1, Madhavan Amutha Selvi, Arunachalam Dayalan
1Department of Chemistry, Loyola College (Autonomous), Sterling Road, Nungambakkam, Chennai 600 034, Tamil Nadu, India.
Abstract:
The asymmetric unit of the title complex, [Co(C(14)H(11)N(2)O(2))(2)Cl(H(2)O)]·2H(2)O or [Co(dpgH)(2)Cl(H(2)O)]·2H(2)O, where dpgH(-) is diphenyl glyoximate, consists of one-half of a [Co(dpgH)(2)Cl(H(2)O)] complex and one solvent water mol-ecule. The complex is completed through inversion symmetry, with the Co(III) atom situated at the centre of symmetry. The coordination geometry around the Co(III) atom is distorted octa-hedral with the four N atoms of the two dpgH(-) ligands forming an approximate square plane with N-Co-N bite angles of 81.13 (14) and 98.87 (14)°. The Cl(-) ligand and the water mol-ecule are disordered in a 1:1 ratio and are in the axial positions, almost perpendicular to the plane of the glyoximate ligands [O-Co-Cl = 175.3 (10)°]. The two glyoximate ligands are linked by strong intra-molecular O-H⋯O hydrogen bonds. In addition, O-H⋯O inter-actions involving the solvent water mol-ecules and O-H⋯N hydrogen-bonding inter-actions are also observed. The solvent water mol-ecule is disordered over five positions with different occupancies.
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