Colloids

Electrostatic Double Layer Interactions

Colloidal particles carrying the same surface charges cause double layer repulsion.

Constant Potential Interactions

 The interaction energy for two spheres of radii  at infinite separation is given as

(28)

where .

For sphere-plate the interaction energy is twice that of sphere-sphere, i.e.,

(29)

The corresponding force (repulsion) is

(30)

For materials with , equation (30) becomes

(31)