For comparison, the ∆E of the inverse Diels-Alder reaction was also computed. The initial guess for the transition state of the Diels-Alder reaction was taken from Ref. . Then, this structure was readjusted at the BLYP-D3BJ/6-31G level of theory. A difference from the electronic energy of the cyclohexene at the same level of theory was taken as ∆E . The resulting value was 17932 cm -1 , similar to that obtained from the MTD simulations.