Activated complex

From Wikipedia, the free encyclopedia

In chemistry an activated complex is a transitional structure in a chemical reaction that results from an effective collision between molecules and that persists while old bonds are breaking and new bonds are forming. It is therefore a range of molecular geometries along the reaction coordinate:

1 Overview
2 Reference
3 See also
4 External links

[edit] Overview

A sketch of a typical reaction profile

When molecules collide, some of their kinetic energy is converted into potential energy within the colliding molecules. If enough energy is converted, the old bonds become sufficiently distorted for the colliding molecules to form an activated complex. New bonds can then begin to form. In this brief interval of bond breakage and bond formation, the collision complex is in a transitional state. Some sort of partial bonding exists in this transitional structure. The exact structure of this complex is often difficult to determine, but is important to understand the mechanism of a reaction.