Effect of the Dielectric Constant on the Double Layer on Clays

A. K. Helmy and I. M. Natale
Universidad Nacional del Sur, 8000 Bahia Blanca, Argentina

Abstract: Electric potentials as a function of distance were calculated for a model of the double layer on clays in which a surface zone a few water molecules thick has a low dielectric constant. This zone is followed by bulk water with a normal dielectric constant. The double layer potentials were found to be lower than those obtained from the Gouy model, in which water has a normal dielectric constant throughout the double layer.

Key Words: Dielectric constant • Double layer potential • Gouy model • Montmorillonite • Water

Clays and Clay Minerals; August 1985 v. 33; no. 4; p. 329-332; DOI: 10.1346/CCMN.1985.0330408
© 1985, The Clay Minerals Society
Clay Minerals Society (www.clays.org)