Figure 4
Average (a) Rwork, (b) Rfree and (c) Rfree − Rwork as a function of perturbation strength (Å) for semi-empirical (PM7), ab initio (HF/6-31G-D3), density functional [RI-BP86/SV(P)] and standard (cctbx) refinement. The average (ten trials per perturbation) starting Rwork values are 0.15, 0.27, 0.35, 0.44 and 0.55, respectively, for each perturbation dose from 0.3 to 1.5 Å. Random noise (5%) was added to Fobs; therefore, R is expected to be around 0.05, which would correspond to the ideal structure. |