Contact potentials and the adhesion of dust

Differences in work function over the surface of a particle can result in dipole characteristics which are important for small particles. Electrostatic deposition orients these dipoles so that coulomb forces exist between adjacent layers of particles, thus producing high adhesive forces. This orientation is confirmed by measurements of contact potentials. Tests of electrostatically deposited dust show adhesive forces which are normally an order of magnitude greater than adhesive forces of the same dust mechanically deposited.