Long-range attractive tail of colloid interaction

To describe rich phenomena of dilute dispersions of highly-charged colloid particles, it is necessary to modify the long-range electric part of the DLVO potential. The screened Coulomb potential of pure repulsion obtained from the Helmholtz free energy in the DLVO theory is replaced by a new screened electric potential with long-range attractive tail derived from the generalized Gibbs free energy which is identified with a total sum of chemical potentials.