The energy barrier is the activation energy of the reaction. A specific process (transition state) can be written in the middle of a reaction. Each transition state has its own energy barrier. The transition state with the largest positive activation energy is called the maximum potential barrier, and the transition state with the smallest positive activation energy is called the minimum potential barrier.
In a chemical reaction limited by kinetics, the activation energy Ea is the difference between the average molar energy of activation collisions and the average molar energy of all collisions, while the energy barrier E is the difference between the zero point energy of activation complex and reactants.