Potential energy curves landscapes

Fig. 1 Conceptual energy landscapes for bound states c confined by sharp activation barriers. Oriented at an angle 9 to the molecular coordinate x, external force / adds a mechanical potential — (/cos 6)x that tilts the landscape and lowers the barrier. For sharp barriers, the energy contours local to barriers—transition states s —are highly curved and change little in shape or location under force, (a) A single barrier under force, (b) A cascade of barriers under force. The inner barrier emerges to dominate kinetics when the outer barrier is driven below it by k T.

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