366 Perturbation Theories for Fluids and Solids
A drawback of the DLVO potential is that it diverges to minus infinity at con-
tact distance, so that near contact the attraction always prevails over repulsion at
short distances and the thermodynamically stable state is always the aggregate state,
although with high repulsive barriers the relaxation of the system to the equilibrium
state may be slow enough as to remain fluid for long time. The problem may be
avoided by defining an effective HS diameter σ ≥ r
max
. This was done by Victor
and Hansen (1985) by splitting the DLVO potential in the form of the WCA and
applying condition (6.73). Then, first-order perturbation theory predicted reversible
coagulation to take place under conditions in qualitativ ...