text: The DLVO theory (named after Boris erjaguin and Lev andau, Evert erwey and Theodoor verbeek) explains the aggregation and kinetic stability of aqueous dispersions quantitatively and describes the force between charged surfaces interacting through a liquid medium.
  It combines the effects of the van der Waals attraction and the electrostatic repulsion due to the so-called double layer of counterions.
  The electrostatic part of the DLVO interaction is computed in the mean field approximation in the limit of low surface potentials - that is when the potential energy of an elementary charge on the surface is much smaller than the thermal energy scale, . For two spheres of radius  each having a charge  (expressed in units of the elementary charge) separated by a center-to-center distance  in a fluid of dielectric constant  containing a concentration  of monovalent ions, the electrostatic potential takes the form of a screened-Coulomb or Yukawa potential,
  where 
  * is the Bjerrum length,
  * is the potential energy,
  * ≈ 2.71828 is Euler's number,
  * is the inverse of the Debye–Hückel screening length ();  is given by , and
  * is the thermal energy scale at absolute temperature