Figure 5: (a) Theoretical predictions of 1D PNP model for the electrostatic exclusion using 2OMF and 2ZFG effective charge profiles from Figure 4 and for the diffusion potential of MgCl2. (b) OmpF channel reversal potential measurements in KCl and MgCl2 versus concentration ratio ( 𝐶 c i s / 𝐶 t r a n s ). In all experiments the concentration on trans side is kept constant at 0.1 M and the concentration on cis side is varied. Measurements were done at pH 6.