In Eq. ( ) , A is the Yukawa pre-factor, which represents the magnitude of electrostatic repulsion as a function of R -colloid radius, ε -dielectric constant of the solution, ѱ -zeta potential on the surface of the colloid and κ -screening length. The screening length in turn is determined from NA -Avogadro's constant, e -Electronic charge, icsolv -Ionic concentration of the solution, εrelative dielectric constant of the solution, ε0permittivity of free space, kB -Boltzmann's constant