Related Experiment Video
Updated: May 4, 2026

Preparation of SNS CobaltII Pincer Model Complexes of Liver Alcohol Dehydrogenase
Published on: March 19, 2020
Di-aqua-dichlorido-bis-(pyridine-κN)cobalt(II)
P S Kannan1, A S Ganeshraja2, K Anbalagan2
1Department of Physics, S. R. R. Engineering College (A. Jeppiaar Institution), Old Mamallapuram Road, Padur, Chennai 603 103, India.
Abstract:
The title mol-ecule, [CoCl2(C5H5N)2(H2O)2], has -1 symmetry with the Co(II) ion situated on an inversion centre. The cation has a distorted octa-hedral coordination environment and is surrounded by two N and two Cl atoms in the equatorial plane, while the coordinating water O atoms occupy the axial positions. The crystal exhibits nonmerohedral twinning with two domain states, the volume fractions of which were refined to 0.883 (2) and 0.117 (3). The crystal packing is stabilized by O-H⋯Cl hydrogen-bond inter-actions, forming two-dimensional networks lying parallel to (001). The crystal packing also features π-π inter-actions between the pyridine rings, with centroid-centroid separations of 3.493 (3) and 3.545 (3) Å.
Related Concept Videos
Coordination Compounds and Nomenclature
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
Valence Bond Theory
Structural Isomerism
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly,...
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Formation of Complex Ions

