unimolekuláris
Unimolekuláris, or unimolecular, refers to processes in which a single molecule undergoes a chemical transformation without requiring a collision with another distinct reactant molecule in the rate-determining step. In simple cases the rate law is first order: rate = k [A]. This contrasts with bimolecular reactions, where the rate depends on the product of the concentrations of two reacting species, and with termolecular reactions that involve three bodies.
In gas-phase kinetics unimolecular reactions are often described by mechanisms in which energy transfer by collisions
Unimolecular processes include various decompositions and isomerizations of molecules, photodissociation, and other energy-driven transformations. They are
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