For both GAs, the fitness of each individual depends on the difference in electronic energy of intermediate 2 and 1, see Figure . As Meyer et al. established using linearenergy scaling relationships following an approach by Busch et al. and Wodrich et al. , the optimal difference in electronic energy ( E) between the two intermediates is in the range of -32.1 and 23.0 kcal mol 1 at the B3LYP-D3BJ/def2-TZVP//B3LYP-D3BJ/3-21 level. We calculate E at the B3LYP-D3BJ/def2-TZVP//B3LYP-D3BJ/3-21 level and convert it to a score between 0 and 1 using a Gaussian function centered around 27.55 kcal mol 1 (µ1) and a standard deviation ( 1) of 6.00 kcal mol 1 , chosen empirically, see Equation . Therefore, the closer the calculated E is to the target value of 27.55 kcal mol 1 the closer the score is to 1.0.