SEARCH Articles Figures Tables Portion of the FMPES associated with rotating methylene groups of cyclobutene at different PP separations under EFEI mechanochemical conditions at f 1,500 pN for the conrotatory pathway. The energies on the surfaces are plotted relative to that of the structures on the disrotatory surface with a PP separation of 3.0 A and torsion of 180 . Solid lines indicate the MEP on each surface. Locations of transition states and products are indicated as TS and P, respectively [Publishers Imprint]