The energy of these entities is lowered by the use of catalysts, as these entities are accessible once the activation energy is added to the reactants.
Protein engineering uses phi value analysis to study the structure of these entities, which are thought always to be aromatic for pericyclic reactions. These entities are predicted to be "early" or "late" by the Hammond postulate, based on whether (*) reactants or products are higher in enthalpy. These entities are located at first-order saddle points on the potential energy surface, as they are depicted as local maxima on reaction coordinate diagrams. The energy of these entities is lowered by the use of catalysts, as these entities are accessible once the activation energy is added to the reactants. For 10 points, name this entity in which all bonds are activated.
Protein engineering uses phi value analysis to study the structure of these entities, which are thought always to be aromatic for pericyclic reactions.
{transition states}