Bond fission, also known as bond cleavage, is the process of breaking a chemical bond, typically a covalent bond, resulting in the splitting of a molecule into two or more fragments

. There are two main types of bond fission:

1. Homolytic Fission (Homolysis)

• The covalent bond breaks evenly, with each atom taking one electron from the shared pair

• This produces two free radicals, each with an unpaired electron

• It requires a significant amount of energy, often supplied by heat, light (such as ultraviolet radiation), or organic peroxides

• Homolytic fission is common in the vapor phase and leads to highly reactive free radicals

2. Heterolytic Fission (Heterolysis)

• The covalent bond breaks unevenly, with one atom taking both electrons from the bond pair, while the other atom gets none

• This results in the formation of ions: one positively charged (cation) and one negatively charged (anion)

• The atom with higher electronegativity usually retains both electrons, becoming the anion

• Heterolytic fission is common in polar molecules and solvents and generally requires more energy than homolytic fission due to the creation of charged species

In summary, bond fission is the breaking of a chemical bond, which can occur either by homolytic cleavage producing radicals or heterolytic cleavage producing ions, with the pathway depending on the nature of the bond and the conditions applied