where M ≈ 1.106 is the Medulung constant of the two dimensional triangular lattice. Equation ( ) can now be solved self-consistently in a combination with the mPB equation. We proceed as follows. For a given value of pK a and ions of each type inside the cell {N i }, we "guess" the mean-electrostatic potential inside the suspension ϕ guess (r). For this guess we calculate the ionic density profiles using Eq. ( ) and pH using Eq. ( ). We then solve Eq. ( ) to obtain Z ef f . Using this value and the ionic density profiles we then recalculate the electrostatic potential using Eq. ( ), and repeat this procedure until convergence is achieved. The full titration curve can be obtained by varying the number of free hydronium ions inside the cell N H for a fixed concentration of salt ions.