FIGURE 2.

(A) Apparent pK_a of Am in a local environment that provides N_Am-H hydrogen bonds for and N_Am hydrogen bonds for NH₃ derived from population analysis of MD trajectories for Am in dilute aqueous solution. The green contour line indicates the equivalence point (pK_a = 7). The diagonal dashed line indicates where N_Am-H = N_Am. (B) Apparent pK_a of Am for a local hydration environment where N_Am-H = N_Am. Note that the equivalence point occurs in an environment providing 3.6 hydrogen bonds or less (see the dotted lines).