Written by the Fiveable Content Team • Last updated August 2025
Written by the Fiveable Content Team • Last updated August 2025
Definition
The activated complex, also known as the transition state, is a temporary and unstable arrangement of atoms formed during a chemical reaction. It represents the highest energy point along the reaction pathway.
A graphical representation showing the energy changes during a chemical reaction, indicating activation energy and the energies of reactants, products, and the activated complex.