In fact, stable clusters (dashed line) are formed with an activation barrier negligible compared to thermal energy. (science.sciencemag.org)
The structure and depth of the indicated minimum remain unknown, as well as the height of the activation barrier for nucleation. (science.sciencemag.org)
«In general a catalyst lowers the activation barrier for a reaction to occur,» Lutterman said. (sciencedaily.com)