Set 2 Set 3 0.90 ± 0.03 (0.86 ± 0.03) 4.16 ± 0.01 (0.81 ± 0.03) 1.51 ± 0.02 (0.87 ± 0.03) Figure : The ψ and φ distributions of the central residues of the alanine pentapeptide, plotted in the form -log(p ψ,φ ) (where p ψ,φ is the probability of a region being occupied). The lighter regions correspond to low probability areas including conformations that are not sampled during the simulation. . The J coupling errors extracted from MD simulations of the alanine pentapeptide are shown in Table , with the φ/ψ distribution shown in Figure and further results given in Section S5.1 of the Supporting Information. Three sets of Karplus parameters are used to evaluate the error and the values in parentheses exclude the 2 J(N, C α ) coupling term.