What Is The Definition Of An Activated Complex?

Activated complex is defined as a state of highest energy level that the molecular compound or compounds reach during their chemical reaction with other compounds. The activated complex is not the final stage of a chemical reaction between two or more compounds – rather it is an intermediary state between the reactants and the produce of reaction. Hence activated complex can be defined as a transitory stage through which the reactants get converted into the final product by reorganizing their internal atomic structure. Thus, we may conclude that a reaction must have distinctively three stages –

(1) Initial stage consisting the reactants
(2) Transitory stage featured by activated complex
(3) Final stage consisting the products of the chemical reaction

For a successful chemical reaction to occur, two or more reactants must collide chemically with each other. This collision must require a minimum level of energy called activation energy. Now as soon as the reactants reach at the level where they could acquire the minimum energy level, they enter into the transition stage, that is, the activated complex is reached.