Figure : Quality of the V MM (λ) correction potential as a function of the order of the polynomial fit to ∂V /∂λ λ for Asp. Panel A shows the fitting error, as a function of fitting order (black line). The gray dashed line shows the average error of calculated ∂V MM /∂λ. In the panel B, the distributions of λ-coordinates for the 3 rd and 7 th order polynomial fits to ∂V /∂λ λ are shown. While with the lower order fit the distribution is significantly rugged, it is nearly flat and yields a uniform distribution for on the [0, 1] interval of the λ-coordinate, when using 7 th order.