Fig. S7.

Dependence of free energy minima on V. Schematic view of the dependence of the free energy of the two minima on the external field estimated using the Eq. 4 (Material and Methods). Voltages are referred as follows: −200 mV, green line; 0 mV, red line; and +200 mV black line. Na⁺ and Cs⁺ systems are shown in A and B, respectively.