Geometrical isomers and optical isomers are two types of stereoisomers found in coordination compounds. Stereoisomers are compounds with the same molecular formula and connectivity but different spatial arrangements of atoms or groups.1. Geometrical isomers: These isomers differ in the relative positions of ligands around the central metal atom. Geometrical isomerism is common in coordination compounds with coordination numbers 4 and 6. The two main types of geometrical isomers are cis and trans isomers.Example: [Co NH3 4Cl2]+In the cis isomer, the two chloride ligands are adjacent to each other, while in the trans isomer, they are opposite each other. The different spatial arrangements of ligands can lead to different chemical and physical properties, such as solubility, color, and reactivity.Significance: Geometrical isomers can have different chemical and physical properties, which can be exploited in various applications, such as catalysis, drug design, and materials science.2. Optical isomers: These isomers are non-superimposable mirror images of each other, like left and right hands. Optical isomers are also called enantiomers or chiral isomers. They occur in coordination compounds with asymmetric arrangements of ligands around the central metal atom.Example: [Co en 3]3+ where en = ethylenediamine The two enantiomers of this complex are non-superimposable mirror images, similar to left and right hands. They rotate plane-polarized light in opposite directions, which is why they are called optical isomers.Significance: Optical isomers can have different biological activities, as enzymes and other biomolecules are often chiral and can selectively interact with one enantiomer over the other. This selectivity is crucial in drug design, as one enantiomer may have therapeutic effects, while the other may be inactive or even harmful. Additionally, optical isomers can be used as chiral catalysts in asymmetric synthesis, enabling the production of enantiomerically pure compounds.In summary, geometrical isomers differ in the relative positions of ligands around the central metal atom, while optical isomers are non-superimposable mirror images of each other. Both types of isomers have significant implications in coordination chemistry, as they can exhibit different chemical, physical, and biological properties.