Homolyse

Homolyse, also known as homolytic cleavage, is a type of bond breaking in chemistry where a covalent bond breaks in such a way that each fragment retains one of the bonding electrons. This process results in the formation of two neutral species, each possessing an unpaired electron. These species are known as free radicals. Homolytic cleavage typically occurs under conditions of high temperature, in the presence of light (photolysis), or with the help of radical initiators such as peroxides. The energy required to break a bond homolytically is known as the bond dissociation energy. This type of reaction is fundamental to many organic reaction mechanisms, including polymerization and combustion. In contrast to heterolytic cleavage, where one fragment takes both electrons from the covalent bond, homolysis produces equally charged fragments. The formation of free radicals is a key step in chain reactions, where a radical initiates a series of transformations by abstracting an atom or group from another molecule, thereby creating a new radical. Understanding homolysis is crucial for predicting the products and understanding the mechanisms of numerous chemical processes.