Particles in the surface region
of a phase are subjected to orienting forces as a result of the anisotropic force field. Polar molecules (e.g. permanent dipoles) may thus be preferentially oriented in the surface region
, while polarizable molecules may be polarized (induced dipoles). The array of oriented polar and/or polarized molecules is called the surface dipole layer with which an electric potential
drop is associated, called the surface potential of the phase.
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook